Added language selection and translation files

frontend/package.json

@@ -10,8 +10,11 @@
     "preview": "vite preview"
   },
   "dependencies": {
+    "i18next": "^25.7.1",
+    "i18next-browser-languagedetector": "^8.2.0",
     "react": "^18.3.1",
     "react-dom": "^18.3.1",
+    "react-i18next": "^16.3.5",
     "react-router-dom": "^6.28.0"
   },
   "devDependencies": {

frontend/src/components/LanguageSelector.tsx

@@ -0,0 +1,56 @@
+import { useTranslation } from 'react-i18next'
+import { LANGUAGES, type LanguageCode } from '@/i18n'
+
+interface LanguageSelectorProps {
+  /** Additional CSS classes */
+  className?: string
+  /** Compact mode - shows only flag and code */
+  compact?: boolean
+}
+
+/**
+ * A dropdown component for selecting the application language.
+ * Uses i18next for language switching and persists choice to localStorage.
+ */
+export default function LanguageSelector({ className = '', compact = false }: LanguageSelectorProps) {
+  const { i18n, t } = useTranslation('common')
+
+  const handleLanguageChange = (e: React.ChangeEvent<HTMLSelectElement>) => {
+    const newLang = e.target.value as LanguageCode
+    i18n.changeLanguage(newLang)
+  }
+
+  return (
+    <div className={`relative ${className}`}>
+      <select
+        value={i18n.language}
+        onChange={handleLanguageChange}
+        className="appearance-none bg-white border border-gray-300 rounded-md pl-3 pr-8 py-1.5 text-sm text-gray-700 hover:border-gray-400 focus:outline-none focus:ring-2 focus:ring-teal-500 focus:border-transparent cursor-pointer"
+        title={t('selectLanguage')}
+        aria-label={t('selectLanguage')}
+      >
+        {LANGUAGES.map((lang) => (
+          <option key={lang.code} value={lang.code}>
+            {compact ? `${lang.flag} ${lang.code.toUpperCase()}` : `${lang.flag} ${lang.label}`}
+          </option>
+        ))}
+      </select>
+      {/* Custom dropdown arrow */}
+      <div className="pointer-events-none absolute inset-y-0 right-0 flex items-center pr-2">
+        <svg
+          className="h-4 w-4 text-gray-400"
+          fill="none"
+          stroke="currentColor"
+          viewBox="0 0 24 24"
+        >
+          <path
+            strokeLinecap="round"
+            strokeLinejoin="round"
+            strokeWidth={2}
+            d="M19 9l-7 7-7-7"
+          />
+        </svg>
+      </div>
+    </div>
+  )
+}

frontend/src/components/Layout.tsx

@@ -1,4 +1,5 @@
 import type { ReactNode } from 'react'
+import { useTranslation } from 'react-i18next'
 import Navbar from './Navbar'
 
 interface LayoutProps {
@@ -6,6 +7,8 @@ interface LayoutProps {
 }
 
 export default function Layout({ children }: LayoutProps) {
+  const { t } = useTranslation('navbar')
+
   return (
     <div className="flex min-h-screen flex-col">
       <Navbar />
@@ -17,8 +20,7 @@ export default function Layout({ children }: LayoutProps) {
       <footer className="border-t border-gray-200 bg-white py-6">
         <div className="mx-auto max-w-7xl px-4 sm:px-6 lg:px-8">
           <p className="text-center text-sm text-gray-500">
-            &copy; {new Date().getFullYear()} Requirements Periodic Table. All rights
-            reserved.
+            &copy; {new Date().getFullYear()} {t('brand')}.
           </p>
         </div>
       </footer>

frontend/src/components/Navbar.tsx

@@ -1,8 +1,11 @@
 import { Link } from 'react-router-dom'
+import { useTranslation } from 'react-i18next'
 import { useAuth } from '@/hooks'
+import LanguageSelector from './LanguageSelector'
 
 export default function Navbar() {
   const { user, isAuthenticated, login, logout } = useAuth()
+  const { t } = useTranslation('navbar')
 
   return (
     <nav className="border-b border-gray-200 bg-white shadow-sm">
@@ -27,23 +30,26 @@ export default function Navbar() {
                 <rect x="9" y="3" width="6" height="4" rx="1" />
                 <path d="M9 12l2 2 4-4" />
               </svg>
-              <span>Requirements Periodic Table</span>
+              <span>{t('brand')}</span>
             </Link>
           </div>
 
           {/* Navigation Links */}
           <div className="flex items-center gap-4">
+            {/* Language Selector */}
+            <LanguageSelector compact />
+            
             {isAuthenticated ? (
               <>
                 <Link
                   to="/dashboard"
                   className="rounded-md px-3 py-2 text-sm font-medium text-gray-700 hover:bg-gray-100 hover:text-gray-900"
                 >
-                  Dashboard
+                  {t('dashboard')}
                 </Link>
                 <div className="flex items-center gap-3">
                   <span className="text-sm text-gray-600">
-                    Hello,{' '}
+                    {t('hello')},{' '}
                     <span className="font-medium text-gray-900">
                       {user?.full_name || user?.preferred_username}
                     </span>
@@ -52,7 +58,7 @@ export default function Navbar() {
                     onClick={logout}
                     className="rounded-md bg-gray-100 px-4 py-2 text-sm font-medium text-gray-700 transition-colors hover:bg-gray-200"
                   >
-                    Logout
+                    {t('logout')}
                   </button>
                 </div>
               </>
@@ -61,7 +67,7 @@ export default function Navbar() {
                 onClick={login}
                 className="rounded-md bg-primary-600 px-4 py-2 text-sm font-medium text-white transition-colors hover:bg-primary-700"
               >
-                Login
+                {t('login')}
               </button>
             )}
           </div>

frontend/src/components/index.ts

@@ -1,3 +1,4 @@
 export { default as Layout } from './Layout'
 export { default as Navbar } from './Navbar'
 export { default as ProtectedRoute } from './ProtectedRoute'
+export { default as LanguageSelector } from './LanguageSelector'

frontend/src/i18n/i18n.d.ts

@@ -0,0 +1,9 @@
+import 'i18next';
+import { resources, defaultNS } from './index';
+
+declare module 'i18next' {
+  interface CustomTypeOptions {
+    defaultNS: typeof defaultNS;
+    resources: typeof resources['en'];
+  }
+}

frontend/src/i18n/index.ts

@@ -0,0 +1,96 @@
+import i18n from 'i18next';
+import { initReactI18next } from 'react-i18next';
+import LanguageDetector from 'i18next-browser-languagedetector';
+
+// Import English translations
+import enCommon from './locales/en/common.json';
+import enNavbar from './locales/en/navbar.json';
+import enHome from './locales/en/home.json';
+import enDashboard from './locales/en/dashboard.json';
+import enRequirements from './locales/en/requirements.json';
+import enRequirementDetail from './locales/en/requirementDetail.json';
+import enAdmin from './locales/en/admin.json';
+import enValidation from './locales/en/validation.json';
+import enErrors from './locales/en/errors.json';
+
+// Import Portuguese translations
+import ptCommon from './locales/pt/common.json';
+import ptNavbar from './locales/pt/navbar.json';
+import ptHome from './locales/pt/home.json';
+import ptDashboard from './locales/pt/dashboard.json';
+import ptRequirements from './locales/pt/requirements.json';
+import ptRequirementDetail from './locales/pt/requirementDetail.json';
+import ptAdmin from './locales/pt/admin.json';
+import ptValidation from './locales/pt/validation.json';
+import ptErrors from './locales/pt/errors.json';
+
+// Define available languages for the language selector
+export const LANGUAGES = [
+  { code: 'en', label: 'English', flag: '🇺🇸' },
+  { code: 'pt', label: 'Português', flag: '🇧🇷' },
+] as const;
+
+export type LanguageCode = typeof LANGUAGES[number]['code'];
+
+// Define resources with all namespaces
+export const resources = {
+  en: {
+    common: enCommon,
+    navbar: enNavbar,
+    home: enHome,
+    dashboard: enDashboard,
+    requirements: enRequirements,
+    requirementDetail: enRequirementDetail,
+    admin: enAdmin,
+    validation: enValidation,
+    errors: enErrors,
+  },
+  pt: {
+    common: ptCommon,
+    navbar: ptNavbar,
+    home: ptHome,
+    dashboard: ptDashboard,
+    requirements: ptRequirements,
+    requirementDetail: ptRequirementDetail,
+    admin: ptAdmin,
+    validation: ptValidation,
+    errors: ptErrors,
+  },
+} as const;
+
+// Define default namespace
+export const defaultNS = 'common';
+
+i18n
+  // Detect user language from localStorage, navigator, etc.
+  .use(LanguageDetector)
+  // Pass i18n instance to react-i18next
+  .use(initReactI18next)
+  // Initialize i18next
+  .init({
+    resources,
+    fallbackLng: 'en',
+    defaultNS,
+    
+    // Language detection options
+    detection: {
+      // Order of language detection methods
+      order: ['localStorage', 'navigator', 'htmlTag'],
+      // Cache user language preference in localStorage
+      caches: ['localStorage'],
+      // Key name in localStorage
+      lookupLocalStorage: 'i18nextLng',
+    },
+
+    interpolation: {
+      // React already escapes values, so we don't need i18next to do it
+      escapeValue: false,
+    },
+
+    // React Suspense support (for future lazy loading)
+    react: {
+      useSuspense: false,
+    },
+  });
+
+export default i18n;

frontend/src/i18n/locales/en/admin.json

@@ -0,0 +1,68 @@
+{
+  "pageTitle": "Admin Panel",
+  "managing": "Managing:",
+  "tabs": {
+    "projectSettings": "Project Settings",
+    "memberRoles": "Member Roles",
+    "relationshipTypes": "Relationship Types"
+  },
+  "backToDashboard": "Back to Dashboard",
+  "noProject": {
+    "title": "No Project Selected",
+    "message": "Please select a project from the dashboard first.",
+    "goToDashboard": "Go to Dashboard"
+  },
+  "projectSettings": {
+    "title": "Project Settings",
+    "projectName": "Project Name",
+    "description": "Description",
+    "saveButton": "Save Changes",
+    "successMessage": "Project updated successfully!",
+    "errorUpdating": "Failed to update project"
+  },
+  "memberRoles": {
+    "title": "Member Roles",
+    "loadingMembers": "Loading members...",
+    "noMembers": "No members found",
+    "tableHeaders": {
+      "user": "User",
+      "role": "Role",
+      "actions": "Actions"
+    },
+    "youBadge": "You",
+    "cannotDemoteSelf": "You cannot demote yourself. Ask another admin to change your role.",
+    "errorUpdating": "Failed to update member role"
+  },
+  "relationshipTypes": {
+    "title": "Relationship Types",
+    "addButton": "+ Add Type",
+    "loadingTypes": "Loading relationship types...",
+    "noTypes": "No relationship types defined yet. Create one to link requirements.",
+    "inverse": "Inverse:",
+    "editButton": "Edit",
+    "deleteButton": "Delete"
+  },
+  "createRelTypeModal": {
+    "title": "Create Relationship Type",
+    "typeName": "Type Name",
+    "typeNamePlaceholder": "e.g., Depends On",
+    "inverseName": "Inverse Name",
+    "inverseNamePlaceholder": "e.g., Depended By",
+    "inverseNameHint": "Optional. The name shown when viewing from the target requirement.",
+    "description": "Description",
+    "createButton": "Create",
+    "errorCreating": "Failed to create relationship type"
+  },
+  "editRelTypeModal": {
+    "title": "Edit Relationship Type",
+    "saveButton": "Save Changes",
+    "errorUpdating": "Failed to update relationship type"
+  },
+  "deleteRelTypeModal": {
+    "title": "Delete Relationship Type",
+    "confirmMessage": "Are you sure you want to delete the relationship type",
+    "warningMessage": "⚠️ This will also delete all requirement links using this type.",
+    "deleteButton": "Delete",
+    "errorDeleting": "Failed to delete relationship type"
+  }
+}

frontend/src/i18n/locales/en/common.json

@@ -0,0 +1,49 @@
+{
+  "save": "Save",
+  "saveChanges": "Save Changes",
+  "saving": "Saving...",
+  "cancel": "Cancel",
+  "delete": "Delete",
+  "deleting": "Deleting...",
+  "edit": "Edit",
+  "close": "Close",
+  "loading": "Loading...",
+  "retry": "Retry",
+  "search": "Search",
+  "clear": "Clear",
+  "filter": "Filter",
+  "create": "Create",
+  "creating": "Creating...",
+  "add": "Add",
+  "remove": "Remove",
+  "yes": "Yes",
+  "no": "No",
+  "none": "None",
+  "unknown": "Unknown",
+  "noResults": "No results found",
+  "required": "Required",
+  "optional": "Optional",
+  "version": "Version",
+  "priority": "Priority",
+  "status": "Status",
+  "date": "Date",
+  "name": "Name",
+  "description": "Description",
+  "actions": "Actions",
+  "details": "Details",
+  "user": "User",
+  "role": "Role",
+  "by": "by",
+  "on": "on",
+  "more": "more",
+  "empty": "Empty",
+  "old": "Old",
+  "new": "New",
+  "total": "Total",
+  "all": "All",
+  "you": "You",
+  "projects": "Projects",
+  "project": "Project",
+  "selectLanguage": "Select language",
+  "logout": "Logout"
+}

frontend/src/i18n/locales/en/dashboard.json

@@ -0,0 +1,67 @@
+{
+  "sidebar": {
+    "title": "Digital Twin",
+    "subtitle": "Requirements Tool",
+    "createRequirement": "Create Requirement",
+    "navigation": "Navigation",
+    "searchRequirements": "Search Requirements",
+    "myRequirements": "My Requirements",
+    "generateReport": "Generate Report",
+    "projectSummary": "Project Summary",
+    "total": "Total",
+    "validated": "Validated"
+  },
+  "header": {
+    "projects": "Projects",
+    "admin": "Admin"
+  },
+  "projectDropdown": {
+    "loading": "Loading...",
+    "noProjectSelected": "No project selected",
+    "noProjectsAvailable": "No projects available",
+    "createNewProject": "+ Create New Project"
+  },
+  "noProjectWarning": {
+    "title": "No Project Selected",
+    "messagePart1": "Please select a project from the dropdown above or",
+    "createProject": "create a new project",
+    "messagePart2": "to get started."
+  },
+  "quickFilters": {
+    "title": "Quick Search Filters",
+    "subtitle": "Click a category to filter requirements",
+    "noGroupsFound": "No groups found",
+    "total": "total"
+  },
+  "needsAttention": {
+    "title": "Needs Attention",
+    "subtitle": "Requirements with denied or partial validation",
+    "viewAll": "View All",
+    "moreRequirements": "more requirements need attention",
+    "by": "by"
+  },
+  "needsRevalidation": {
+    "title": "Needs Revalidation",
+    "subtitle": "Requirements updated since last validation",
+    "viewAll": "View All",
+    "moreRequirements": "more requirements need revalidation",
+    "versionBehind": "version behind",
+    "versionsBehind": "versions behind",
+    "lastValidatedBy": "Last validated by",
+    "by": "by"
+  },
+  "allClear": {
+    "title": "All Clear!",
+    "message": "No requirements need attention. All validations are either approved or pending review."
+  },
+  "createProject": {
+    "title": "Create New Project",
+    "projectName": "Project Name",
+    "projectNamePlaceholder": "Enter project name",
+    "description": "Description",
+    "descriptionPlaceholder": "Enter project description (optional)",
+    "createButton": "Create Project",
+    "creating": "Creating...",
+    "errorCreating": "Failed to create project. Please try again."
+  }
+}

frontend/src/i18n/locales/en/errors.json

@@ -0,0 +1,11 @@
+{
+  "generic": "An error occurred. Please try again.",
+  "loadFailed": "Failed to load data. Please try again.",
+  "saveFailed": "Failed to save. Please try again.",
+  "deleteFailed": "Failed to delete. Please try again.",
+  "createFailed": "Failed to create. Please try again.",
+  "unauthorized": "You are not authorized to perform this action.",
+  "notFound": "The requested resource was not found.",
+  "networkError": "Network error. Please check your connection.",
+  "sessionExpired": "Your session has expired. Please log in again."
+}

frontend/src/i18n/locales/en/home.json

@@ -0,0 +1,5 @@
+{
+  "title": "Requirements Periodic Table",
+  "subtitle": "Manage and track your project requirements.",
+  "goToDashboard": "Go to Dashboard"
+}

frontend/src/i18n/locales/en/navbar.json

@@ -0,0 +1,7 @@
+{
+  "brand": "Requirements Periodic Table",
+  "dashboard": "Dashboard",
+  "hello": "Hello",
+  "logout": "Logout",
+  "login": "Login"
+}

frontend/src/i18n/locales/en/requirementDetail.json

@@ -0,0 +1,155 @@
+{
+  "pageTitle": "Digital Twin Requirements Tool",
+  "breadcrumb": {
+    "search": "Search",
+    "details": "Details"
+  },
+  "loadingRequirement": "Loading requirement...",
+  "requirementNotFound": "Requirement not found",
+  "noRequirementId": "No requirement ID provided",
+  "backToRequirements": "Back to Requirements",
+  "errorLoading": "Failed to load requirement. Please try again.",
+  "draft": {
+    "badge": "Draft - Not Finalized",
+    "title": "Draft Requirement",
+    "message": "This requirement is still in draft status and is not finalized. It may be subject to changes."
+  },
+  "tabs": {
+    "description": "Description",
+    "relationships": "Relationships",
+    "acceptanceCriteria": "Acceptance Criteria",
+    "sharedComments": "Shared Comments",
+    "validate": "Validate",
+    "history": "History"
+  },
+  "description": {
+    "title": "Description",
+    "version": "Version:",
+    "status": "Status:",
+    "validationStatus": "Validation Status:",
+    "author": "Author:",
+    "lastEditedBy": "Last Edited By:",
+    "created": "Created:",
+    "lastUpdated": "Last Updated:",
+    "noDescription": "No description provided.",
+    "editButton": "Edit"
+  },
+  "relationships": {
+    "title": "Relationships",
+    "addButton": "Add Relationship",
+    "noTypesWarning": "No relationship types have been defined for this project. Contact an administrator to set up relationship types.",
+    "loadingRelationships": "Loading relationships...",
+    "noRelationships": "No relationships defined yet.",
+    "tableHeaders": {
+      "direction": "Direction",
+      "type": "Type",
+      "linkedRequirement": "Linked Requirement",
+      "createdBy": "Created By",
+      "date": "Date",
+      "actions": "Actions"
+    },
+    "outgoing": "→ Outgoing",
+    "incoming": "← Incoming"
+  },
+  "acceptanceCriteria": {
+    "title": "Acceptance Criteria",
+    "noCriteria": "No acceptance criteria defined yet.",
+    "addButton": "Add Criterion"
+  },
+  "comments": {
+    "title": "Shared Comments",
+    "placeholder": "Add a comment...",
+    "postButton": "Post Comment",
+    "posting": "Posting...",
+    "noComments": "No comments yet. Be the first to comment!",
+    "loadingComments": "Loading comments...",
+    "reply": "Reply",
+    "cancelReply": "Cancel Reply",
+    "replyPlaceholder": "Write a reply...",
+    "postReply": "Post Reply",
+    "errorPosting": "Failed to post comment. Please try again.",
+    "errorPostingReply": "Failed to post reply. Please try again.",
+    "roles": {
+      "editor": "Editor",
+      "auditor": "Auditor",
+      "admin": "Project Admin",
+      "user": "User"
+    }
+  },
+  "validate": {
+    "title": "Validate Requirement",
+    "currentStatus": "Current Status:",
+    "requirementVersion": "Requirement Version:",
+    "lastValidatedBy": "Last validated by",
+    "staleWarning": "This requirement was modified after the last validation (validated at version {{validationVersion}}, current version {{currentVersion}}).",
+    "submitTitle": "Submit Validation",
+    "statusLabel": "Validation Status",
+    "selectStatus": "Select a status...",
+    "commentLabel": "Comment",
+    "commentPlaceholder": "Add a comment explaining your decision (optional but recommended)",
+    "submitButton": "Submit Validation",
+    "submitting": "Submitting...",
+    "errorSubmitting": "Failed to submit validation. Please try again.",
+    "historyTitle": "Validation History",
+    "loadingHistory": "Loading history...",
+    "noHistory": "No validation history yet.",
+    "tableHeaders": {
+      "date": "Date",
+      "status": "Status",
+      "version": "Version",
+      "validator": "Validator",
+      "comment": "Comment"
+    },
+    "noComment": "No comment"
+  },
+  "history": {
+    "title": "Version History",
+    "originalAuthor": "Original Author:",
+    "loadingHistory": "Loading history...",
+    "noHistory": "No history yet. History is recorded when the requirement is edited or relationships change.",
+    "requirementEdited": "Requirement edited",
+    "linkCreated": "Link Created",
+    "linkRemoved": "Link Removed",
+    "groupAdded": "Group Added",
+    "groupRemoved": "Group Removed",
+    "noChangesDetected": "No visible changes detected (may be a group-only change).",
+    "showLess": "Show less",
+    "showFullDiff": "Show full diff",
+    "deletedRequirement": "Deleted Requirement",
+    "unknownGroup": "Unknown Group"
+  },
+  "addRelationshipModal": {
+    "title": "Add Relationship",
+    "relationshipType": "Relationship Type",
+    "selectType": "Select a relationship type...",
+    "targetRequirement": "Target Requirement",
+    "searchPlaceholder": "Search by tag code or name...",
+    "selected": "Selected:",
+    "createButton": "Create Relationship",
+    "errorCreating": "Failed to create link. Please try again."
+  },
+  "editModal": {
+    "title": "Edit Requirement",
+    "loadingOptions": "Loading options...",
+    "name": "Name",
+    "tag": "Tag",
+    "selectTag": "Select a tag...",
+    "priority": "Priority",
+    "noPriority": "No priority",
+    "status": "Status",
+    "draftNote": "Draft requirements are not finalized and marked with a visual indicator.",
+    "description": "Description",
+    "groups": "Groups",
+    "noGroupsAvailable": "No groups available",
+    "errorSaving": "Failed to save changes. Please try again.",
+    "nameTagRequired": "Name and Tag are required"
+  },
+  "deleteModal": {
+    "deleteComment": "Delete Comment",
+    "deleteReply": "Delete Reply",
+    "deleteRelationship": "Delete Relationship",
+    "confirmDeleteComment": "Are you sure you want to delete this comment? This will also hide all replies.",
+    "confirmDeleteReply": "Are you sure you want to delete this reply?",
+    "confirmDeleteRelationship": "Are you sure you want to delete this relationship? This action cannot be undone."
+  }
+}

frontend/src/i18n/locales/en/requirements.json

@@ -0,0 +1,87 @@
+{
+  "header": {
+    "title": "Digital Twin Requirements Tool"
+  },
+  "breadcrumb": {
+    "projects": "Projects",
+    "searchRequirements": "Search Requirements"
+  },
+  "noProjectSelected": {
+    "title": "No Project Selected",
+    "message": "Please select a project from the dashboard to view requirements.",
+    "goToDashboard": "Go to Dashboard"
+  },
+  "loadingRequirements": "Loading requirements...",
+  "newRequirement": "New Requirement",
+  "deleted": "Deleted",
+  "searchPlaceholder": "Search for a requirement tag or title",
+  "noRequirementsFound": "No requirements found matching your criteria.",
+  "filters": {
+    "filterGroup": "Filter Group",
+    "filterValidationStatus": "Filter Validation Status",
+    "showingNeedsRevalidation": "Showing: Needs Revalidation",
+    "showingNeedsAttention": "Showing: Needs Attention",
+    "needsRevalidation": "Needs Revalidation",
+    "statuses": {
+      "approved": "Approved",
+      "denied": "Denied",
+      "partiallyApproved": "Partially Approved",
+      "notValidated": "Not Validated"
+    }
+  },
+  "orderBy": {
+    "label": "Order by",
+    "date": "Date",
+    "priority": "Priority",
+    "name": "Name"
+  },
+  "caption": {
+    "title": "Tag Caption",
+    "viewCaptions": "View tag captions"
+  },
+  "requirement": {
+    "draft": "Draft",
+    "draftTooltip": "This requirement is still in draft and not finalized",
+    "noGroups": "No groups",
+    "more": "more",
+    "stale": "Stale",
+    "staleTooltip": "Requirement was modified after validation",
+    "by": "by",
+    "priority": "Priority",
+    "version": "Version"
+  },
+  "deletedPanel": {
+    "title": "Deleted Requirements",
+    "noDeleted": "No deleted requirements found.",
+    "deletedWillAppear": "Deleted requirements will appear here.",
+    "unnamed": "Unnamed Requirement",
+    "originalId": "Original ID",
+    "deletedAt": "Deleted",
+    "deletedBy": "Deleted by",
+    "footerNote": "Deleted requirements are preserved in history for auditing purposes."
+  },
+  "deleteModal": {
+    "title": "Delete Requirement",
+    "confirmMessage": "Are you sure you want to delete the requirement",
+    "explanation": "This action will move the requirement to the deleted items. You can view deleted requirements from the \"Deleted\" panel.",
+    "deleting": "Deleting..."
+  },
+  "createModal": {
+    "title": "New Requirement",
+    "tag": "Tag",
+    "selectTag": "Select a tag...",
+    "name": "Name",
+    "namePlaceholder": "Enter requirement name",
+    "description": "Description",
+    "descriptionPlaceholder": "Enter requirement description (optional)",
+    "priority": "Priority",
+    "selectPriority": "Select a priority (optional)...",
+    "groups": "Groups",
+    "createButton": "Create Requirement",
+    "creating": "Creating...",
+    "errorCreating": "Failed to create requirement. Please try again.",
+    "noProjectSelected": "No project selected",
+    "nameRequired": "Requirement name is required",
+    "tagRequired": "Please select a tag"
+  }
+}

frontend/src/i18n/locales/en/validation.json

@@ -0,0 +1,7 @@
+{
+  "approved": "Approved",
+  "denied": "Denied",
+  "partial": "Partial",
+  "partiallyApproved": "Partially Approved",
+  "notValidated": "Not Validated"
+}

frontend/src/i18n/locales/pt/admin.json

@@ -0,0 +1,68 @@
+{
+  "pageTitle": "Painel de Administração",
+  "managing": "Gerenciando:",
+  "tabs": {
+    "projectSettings": "Configurações do Projeto",
+    "memberRoles": "Funções dos Membros",
+    "relationshipTypes": "Tipos de Relacionamento"
+  },
+  "backToDashboard": "Voltar ao Painel",
+  "noProject": {
+    "title": "Nenhum Projeto Selecionado",
+    "message": "Por favor, selecione um projeto no painel primeiro.",
+    "goToDashboard": "Ir para o Painel"
+  },
+  "projectSettings": {
+    "title": "Configurações do Projeto",
+    "projectName": "Nome do Projeto",
+    "description": "Descrição",
+    "saveButton": "Salvar Alterações",
+    "successMessage": "Projeto atualizado com sucesso!",
+    "errorUpdating": "Falha ao atualizar projeto"
+  },
+  "memberRoles": {
+    "title": "Funções dos Membros",
+    "loadingMembers": "Carregando membros...",
+    "noMembers": "Nenhum membro encontrado",
+    "tableHeaders": {
+      "user": "Usuário",
+      "role": "Função",
+      "actions": "Ações"
+    },
+    "youBadge": "Você",
+    "cannotDemoteSelf": "Você não pode rebaixar a si mesmo. Peça a outro administrador para alterar sua função.",
+    "errorUpdating": "Falha ao atualizar função do membro"
+  },
+  "relationshipTypes": {
+    "title": "Tipos de Relacionamento",
+    "addButton": "+ Adicionar Tipo",
+    "loadingTypes": "Carregando tipos de relacionamento...",
+    "noTypes": "Nenhum tipo de relacionamento definido ainda. Crie um para vincular requisitos.",
+    "inverse": "Inverso:",
+    "editButton": "Editar",
+    "deleteButton": "Excluir"
+  },
+  "createRelTypeModal": {
+    "title": "Criar Tipo de Relacionamento",
+    "typeName": "Nome do Tipo",
+    "typeNamePlaceholder": "ex.: Depende De",
+    "inverseName": "Nome Inverso",
+    "inverseNamePlaceholder": "ex.: É Dependência De",
+    "inverseNameHint": "Opcional. O nome mostrado ao visualizar do requisito de destino.",
+    "description": "Descrição",
+    "createButton": "Criar",
+    "errorCreating": "Falha ao criar tipo de relacionamento"
+  },
+  "editRelTypeModal": {
+    "title": "Editar Tipo de Relacionamento",
+    "saveButton": "Salvar Alterações",
+    "errorUpdating": "Falha ao atualizar tipo de relacionamento"
+  },
+  "deleteRelTypeModal": {
+    "title": "Excluir Tipo de Relacionamento",
+    "confirmMessage": "Tem certeza de que deseja excluir o tipo de relacionamento",
+    "warningMessage": "⚠️ Isso também excluirá todos os links de requisitos usando este tipo.",
+    "deleteButton": "Excluir",
+    "errorDeleting": "Falha ao excluir tipo de relacionamento"
+  }
+}

frontend/src/i18n/locales/pt/common.json

@@ -0,0 +1,49 @@
+{
+  "save": "Salvar",
+  "saveChanges": "Salvar Alterações",
+  "saving": "Salvando...",
+  "cancel": "Cancelar",
+  "delete": "Excluir",
+  "deleting": "Excluindo...",
+  "edit": "Editar",
+  "close": "Fechar",
+  "loading": "Carregando...",
+  "retry": "Tentar Novamente",
+  "search": "Buscar",
+  "clear": "Limpar",
+  "filter": "Filtrar",
+  "create": "Criar",
+  "creating": "Criando...",
+  "add": "Adicionar",
+  "remove": "Remover",
+  "yes": "Sim",
+  "no": "Não",
+  "none": "Nenhum",
+  "unknown": "Desconhecido",
+  "noResults": "Nenhum resultado encontrado",
+  "required": "Obrigatório",
+  "optional": "Opcional",
+  "version": "Versão",
+  "priority": "Prioridade",
+  "status": "Status",
+  "date": "Data",
+  "name": "Nome",
+  "description": "Descrição",
+  "actions": "Ações",
+  "details": "Detalhes",
+  "user": "Usuário",
+  "role": "Função",
+  "by": "por",
+  "on": "em",
+  "more": "mais",
+  "empty": "Vazio",
+  "old": "Antigo",
+  "new": "Novo",
+  "total": "Total",
+  "all": "Todos",
+  "you": "Você",
+  "projects": "Projetos",
+  "project": "Projeto",
+  "selectLanguage": "Selecionar idioma",
+  "logout": "Sair"
+}

frontend/src/i18n/locales/pt/dashboard.json

@@ -0,0 +1,67 @@
+{
+  "sidebar": {
+    "title": "Digital Twin",
+    "subtitle": "Ferramenta de Requisitos",
+    "createRequirement": "Criar Requisito",
+    "navigation": "Navegação",
+    "searchRequirements": "Buscar Requisitos",
+    "myRequirements": "Meus Requisitos",
+    "generateReport": "Gerar Relatório",
+    "projectSummary": "Resumo do Projeto",
+    "total": "Total",
+    "validated": "Validados"
+  },
+  "header": {
+    "projects": "Projetos",
+    "admin": "Admin"
+  },
+  "projectDropdown": {
+    "loading": "Carregando...",
+    "noProjectSelected": "Nenhum projeto selecionado",
+    "noProjectsAvailable": "Nenhum projeto disponível",
+    "createNewProject": "+ Criar Novo Projeto"
+  },
+  "noProjectWarning": {
+    "title": "Nenhum Projeto Selecionado",
+    "messagePart1": "Por favor, selecione um projeto no menu acima ou",
+    "createProject": "crie um novo projeto",
+    "messagePart2": "para começar."
+  },
+  "quickFilters": {
+    "title": "Filtros Rápidos de Busca",
+    "subtitle": "Clique em uma categoria para filtrar requisitos",
+    "noGroupsFound": "Nenhum grupo encontrado",
+    "total": "total"
+  },
+  "needsAttention": {
+    "title": "Precisa de Atenção",
+    "subtitle": "Requisitos com validação negada ou parcial",
+    "viewAll": "Ver Todos",
+    "moreRequirements": "mais requisitos precisam de atenção",
+    "by": "por"
+  },
+  "needsRevalidation": {
+    "title": "Precisa de Revalidação",
+    "subtitle": "Requisitos atualizados desde a última validação",
+    "viewAll": "Ver Todos",
+    "moreRequirements": "mais requisitos precisam de revalidação",
+    "versionBehind": "versão atrás",
+    "versionsBehind": "versões atrás",
+    "lastValidatedBy": "Última validação por",
+    "by": "por"
+  },
+  "allClear": {
+    "title": "Tudo Certo!",
+    "message": "Nenhum requisito precisa de atenção. Todas as validações estão aprovadas ou pendentes de revisão."
+  },
+  "createProject": {
+    "title": "Criar Novo Projeto",
+    "projectName": "Nome do Projeto",
+    "projectNamePlaceholder": "Digite o nome do projeto",
+    "description": "Descrição",
+    "descriptionPlaceholder": "Digite a descrição do projeto (opcional)",
+    "createButton": "Criar Projeto",
+    "creating": "Criando...",
+    "errorCreating": "Falha ao criar projeto. Por favor, tente novamente."
+  }
+}

frontend/src/i18n/locales/pt/errors.json

@@ -0,0 +1,11 @@
+{
+  "generic": "Ocorreu um erro. Por favor, tente novamente.",
+  "loadFailed": "Falha ao carregar dados. Por favor, tente novamente.",
+  "saveFailed": "Falha ao salvar. Por favor, tente novamente.",
+  "deleteFailed": "Falha ao excluir. Por favor, tente novamente.",
+  "createFailed": "Falha ao criar. Por favor, tente novamente.",
+  "unauthorized": "Você não está autorizado a realizar esta ação.",
+  "notFound": "O recurso solicitado não foi encontrado.",
+  "networkError": "Erro de rede. Por favor, verifique sua conexão.",
+  "sessionExpired": "Sua sessão expirou. Por favor, faça login novamente."
+}

frontend/src/i18n/locales/pt/home.json

@@ -0,0 +1,5 @@
+{
+  "title": "Tabela Periódica de Requisitos",
+  "subtitle": "Gerencie e acompanhe os requisitos do seu projeto.",
+  "goToDashboard": "Ir para o Painel"
+}

frontend/src/i18n/locales/pt/navbar.json

@@ -0,0 +1,7 @@
+{
+  "brand": "Tabela Periódica de Requisitos",
+  "dashboard": "Painel",
+  "hello": "Olá",
+  "logout": "Sair",
+  "login": "Entrar"
+}

frontend/src/i18n/locales/pt/requirementDetail.json

@@ -0,0 +1,155 @@
+{
+  "pageTitle": "Ferramenta de Requisitos Digital Twin",
+  "breadcrumb": {
+    "search": "Buscar",
+    "details": "Detalhes"
+  },
+  "loadingRequirement": "Carregando requisito...",
+  "requirementNotFound": "Requisito não encontrado",
+  "noRequirementId": "Nenhum ID de requisito fornecido",
+  "backToRequirements": "Voltar aos Requisitos",
+  "errorLoading": "Falha ao carregar requisito. Por favor, tente novamente.",
+  "draft": {
+    "badge": "Rascunho - Não Finalizado",
+    "title": "Requisito em Rascunho",
+    "message": "Este requisito ainda está em status de rascunho e não foi finalizado. Pode estar sujeito a alterações."
+  },
+  "tabs": {
+    "description": "Descrição",
+    "relationships": "Relacionamentos",
+    "acceptanceCriteria": "Critérios de Aceitação",
+    "sharedComments": "Comentários Compartilhados",
+    "validate": "Validar",
+    "history": "Histórico"
+  },
+  "description": {
+    "title": "Descrição",
+    "version": "Versão:",
+    "status": "Status:",
+    "validationStatus": "Status de Validação:",
+    "author": "Autor:",
+    "lastEditedBy": "Última Edição Por:",
+    "created": "Criado:",
+    "lastUpdated": "Última Atualização:",
+    "noDescription": "Nenhuma descrição fornecida.",
+    "editButton": "Editar"
+  },
+  "relationships": {
+    "title": "Relacionamentos",
+    "addButton": "Adicionar Relacionamento",
+    "noTypesWarning": "Nenhum tipo de relacionamento foi definido para este projeto. Contate um administrador para configurar os tipos de relacionamento.",
+    "loadingRelationships": "Carregando relacionamentos...",
+    "noRelationships": "Nenhum relacionamento definido ainda.",
+    "tableHeaders": {
+      "direction": "Direção",
+      "type": "Tipo",
+      "linkedRequirement": "Requisito Vinculado",
+      "createdBy": "Criado Por",
+      "date": "Data",
+      "actions": "Ações"
+    },
+    "outgoing": "→ Saída",
+    "incoming": "← Entrada"
+  },
+  "acceptanceCriteria": {
+    "title": "Critérios de Aceitação",
+    "noCriteria": "Nenhum critério de aceitação definido ainda.",
+    "addButton": "Adicionar Critério"
+  },
+  "comments": {
+    "title": "Comentários Compartilhados",
+    "placeholder": "Adicionar um comentário...",
+    "postButton": "Publicar Comentário",
+    "posting": "Publicando...",
+    "noComments": "Nenhum comentário ainda. Seja o primeiro a comentar!",
+    "loadingComments": "Carregando comentários...",
+    "reply": "Responder",
+    "cancelReply": "Cancelar Resposta",
+    "replyPlaceholder": "Escreva uma resposta...",
+    "postReply": "Publicar Resposta",
+    "errorPosting": "Falha ao publicar comentário. Por favor, tente novamente.",
+    "errorPostingReply": "Falha ao publicar resposta. Por favor, tente novamente.",
+    "roles": {
+      "editor": "Editor",
+      "auditor": "Auditor",
+      "admin": "Admin do Projeto",
+      "user": "Usuário"
+    }
+  },
+  "validate": {
+    "title": "Validar Requisito",
+    "currentStatus": "Status Atual:",
+    "requirementVersion": "Versão do Requisito:",
+    "lastValidatedBy": "Última validação por",
+    "staleWarning": "Este requisito foi modificado após a última validação (validado na versão {{validationVersion}}, versão atual {{currentVersion}}).",
+    "submitTitle": "Enviar Validação",
+    "statusLabel": "Status de Validação",
+    "selectStatus": "Selecione um status...",
+    "commentLabel": "Comentário",
+    "commentPlaceholder": "Adicione um comentário explicando sua decisão (opcional, mas recomendado)",
+    "submitButton": "Enviar Validação",
+    "submitting": "Enviando...",
+    "errorSubmitting": "Falha ao enviar validação. Por favor, tente novamente.",
+    "historyTitle": "Histórico de Validação",
+    "loadingHistory": "Carregando histórico...",
+    "noHistory": "Nenhum histórico de validação ainda.",
+    "tableHeaders": {
+      "date": "Data",
+      "status": "Status",
+      "version": "Versão",
+      "validator": "Validador",
+      "comment": "Comentário"
+    },
+    "noComment": "Sem comentário"
+  },
+  "history": {
+    "title": "Histórico de Versões",
+    "originalAuthor": "Autor Original:",
+    "loadingHistory": "Carregando histórico...",
+    "noHistory": "Nenhum histórico ainda. O histórico é registrado quando o requisito é editado ou os relacionamentos mudam.",
+    "requirementEdited": "Requisito editado",
+    "linkCreated": "Link Criado",
+    "linkRemoved": "Link Removido",
+    "groupAdded": "Grupo Adicionado",
+    "groupRemoved": "Grupo Removido",
+    "noChangesDetected": "Nenhuma alteração visível detectada (pode ser uma alteração apenas de grupo).",
+    "showLess": "Mostrar menos",
+    "showFullDiff": "Mostrar diferença completa",
+    "deletedRequirement": "Requisito Excluído",
+    "unknownGroup": "Grupo Desconhecido"
+  },
+  "addRelationshipModal": {
+    "title": "Adicionar Relacionamento",
+    "relationshipType": "Tipo de Relacionamento",
+    "selectType": "Selecione um tipo de relacionamento...",
+    "targetRequirement": "Requisito de Destino",
+    "searchPlaceholder": "Buscar por código de tag ou nome...",
+    "selected": "Selecionado:",
+    "createButton": "Criar Relacionamento",
+    "errorCreating": "Falha ao criar link. Por favor, tente novamente."
+  },
+  "editModal": {
+    "title": "Editar Requisito",
+    "loadingOptions": "Carregando opções...",
+    "name": "Nome",
+    "tag": "Tag",
+    "selectTag": "Selecione uma tag...",
+    "priority": "Prioridade",
+    "noPriority": "Sem prioridade",
+    "status": "Status",
+    "draftNote": "Requisitos em rascunho não estão finalizados e são marcados com um indicador visual.",
+    "description": "Descrição",
+    "groups": "Grupos",
+    "noGroupsAvailable": "Nenhum grupo disponível",
+    "errorSaving": "Falha ao salvar alterações. Por favor, tente novamente.",
+    "nameTagRequired": "Nome e Tag são obrigatórios"
+  },
+  "deleteModal": {
+    "deleteComment": "Excluir Comentário",
+    "deleteReply": "Excluir Resposta",
+    "deleteRelationship": "Excluir Relacionamento",
+    "confirmDeleteComment": "Tem certeza de que deseja excluir este comentário? Isso também ocultará todas as respostas.",
+    "confirmDeleteReply": "Tem certeza de que deseja excluir esta resposta?",
+    "confirmDeleteRelationship": "Tem certeza de que deseja excluir este relacionamento? Esta ação não pode ser desfeita."
+  }
+}

frontend/src/i18n/locales/pt/requirements.json

@@ -0,0 +1,87 @@
+{
+  "header": {
+    "title": "Ferramenta de Requisitos Digital Twin"
+  },
+  "breadcrumb": {
+    "projects": "Projetos",
+    "searchRequirements": "Buscar Requisitos"
+  },
+  "noProjectSelected": {
+    "title": "Nenhum Projeto Selecionado",
+    "message": "Por favor, selecione um projeto no painel para visualizar os requisitos.",
+    "goToDashboard": "Ir para o Painel"
+  },
+  "loadingRequirements": "Carregando requisitos...",
+  "newRequirement": "Novo Requisito",
+  "deleted": "Excluídos",
+  "searchPlaceholder": "Buscar por código de tag ou título do requisito",
+  "noRequirementsFound": "Nenhum requisito encontrado com os critérios selecionados.",
+  "filters": {
+    "filterGroup": "Filtrar Grupo",
+    "filterValidationStatus": "Filtrar Status de Validação",
+    "showingNeedsRevalidation": "Mostrando: Precisa de Revalidação",
+    "showingNeedsAttention": "Mostrando: Precisa de Atenção",
+    "needsRevalidation": "Precisa de Revalidação",
+    "statuses": {
+      "approved": "Aprovado",
+      "denied": "Negado",
+      "partiallyApproved": "Parcialmente Aprovado",
+      "notValidated": "Não Validado"
+    }
+  },
+  "orderBy": {
+    "label": "Ordenar por",
+    "date": "Data",
+    "priority": "Prioridade",
+    "name": "Nome"
+  },
+  "caption": {
+    "title": "Legenda das Tags",
+    "viewCaptions": "Ver legendas das tags"
+  },
+  "requirement": {
+    "draft": "Rascunho",
+    "draftTooltip": "Este requisito ainda está em rascunho e não foi finalizado",
+    "noGroups": "Sem grupos",
+    "more": "mais",
+    "stale": "Desatualizado",
+    "staleTooltip": "O requisito foi modificado após a validação",
+    "by": "por",
+    "priority": "Prioridade",
+    "version": "Versão"
+  },
+  "deletedPanel": {
+    "title": "Requisitos Excluídos",
+    "noDeleted": "Nenhum requisito excluído encontrado.",
+    "deletedWillAppear": "Requisitos excluídos aparecerão aqui.",
+    "unnamed": "Requisito sem nome",
+    "originalId": "ID Original",
+    "deletedAt": "Excluído",
+    "deletedBy": "Excluído por",
+    "footerNote": "Requisitos excluídos são preservados no histórico para fins de auditoria."
+  },
+  "deleteModal": {
+    "title": "Excluir Requisito",
+    "confirmMessage": "Tem certeza de que deseja excluir o requisito",
+    "explanation": "Esta ação moverá o requisito para os itens excluídos. Você pode visualizar os requisitos excluídos no painel \"Excluídos\".",
+    "deleting": "Excluindo..."
+  },
+  "createModal": {
+    "title": "Novo Requisito",
+    "tag": "Tag",
+    "selectTag": "Selecione uma tag...",
+    "name": "Nome",
+    "namePlaceholder": "Digite o nome do requisito",
+    "description": "Descrição",
+    "descriptionPlaceholder": "Digite a descrição do requisito (opcional)",
+    "priority": "Prioridade",
+    "selectPriority": "Selecione uma prioridade (opcional)...",
+    "groups": "Grupos",
+    "createButton": "Criar Requisito",
+    "creating": "Criando...",
+    "errorCreating": "Falha ao criar requisito. Por favor, tente novamente.",
+    "noProjectSelected": "Nenhum projeto selecionado",
+    "nameRequired": "O nome do requisito é obrigatório",
+    "tagRequired": "Por favor, selecione uma tag"
+  }
+}

frontend/src/i18n/locales/pt/validation.json

@@ -0,0 +1,7 @@
+{
+  "approved": "Aprovado",
+  "denied": "Negado",
+  "partial": "Parcial",
+  "partiallyApproved": "Parcialmente Aprovado",
+  "notValidated": "Não Validado"
+}

frontend/src/main.tsx

@@ -5,6 +5,9 @@ import App from './App'
 import { AuthProvider, ProjectProvider } from '@/context'
 import './index.css'
 
+// Initialize i18n before rendering
+import './i18n'
+
 // Global fetch interceptor to handle 401 Unauthorized responses
 // This intercepts all fetch calls and attempts silent refresh before redirecting
 const originalFetch = window.fetch

frontend/src/pages/AdminPage.tsx

@@ -1,5 +1,6 @@
 import { useState, useEffect } from 'react'
 import { useNavigate } from 'react-router-dom'
+import { useTranslation } from 'react-i18next'
 import { useAuth, useProject } from '@/hooks'
 import {
   projectService,
@@ -13,6 +14,8 @@ import {
 type TabType = 'project' | 'members' | 'relationships'
 
 export default function AdminPage() {
+  const { t } = useTranslation('admin')
+  const { t: tCommon } = useTranslation('common')
   const { user } = useAuth()
   const { currentProject, setCurrentProject } = useProject()
   const navigate = useNavigate()
@@ -291,13 +294,13 @@ export default function AdminPage() {
     return (
       <div className="min-h-screen bg-white flex items-center justify-center">
         <div className="text-center">
-          <h2 className="text-xl font-semibold text-gray-700 mb-2">No Project Selected</h2>
-          <p className="text-gray-500 mb-4">Please select a project from the dashboard first.</p>
+          <h2 className="text-xl font-semibold text-gray-700 mb-2">{t('noProject.title')}</h2>
+          <p className="text-gray-500 mb-4">{t('noProject.message')}</p>
           <button
             onClick={() => navigate('/dashboard')}
             className="px-4 py-2 bg-teal-600 text-white rounded hover:bg-teal-700"
           >
-            Go to Dashboard
+            {t('noProject.goToDashboard')}
           </button>
         </div>
       </div>
@@ -308,9 +311,9 @@ export default function AdminPage() {
     <div className="min-h-screen bg-white">
       {/* Header */}
       <header className="py-6 text-center border-b border-gray-200">
-        <h1 className="text-3xl font-semibold text-teal-700">Admin Panel</h1>
+        <h1 className="text-3xl font-semibold text-teal-700">{t('pageTitle')}</h1>
         <p className="text-gray-500 mt-1">
-          Managing: <span className="font-medium">{currentProject.project_name}</span>
+          {t('managing')} <span className="font-medium">{currentProject.project_name}</span>
         </p>
       </header>
 
@@ -326,7 +329,7 @@ export default function AdminPage() {
                   : 'border-transparent text-gray-500 hover:text-gray-700'
               }`}
             >
-              Project Settings
+              {t('tabs.projectSettings')}
             </button>
             <button
               onClick={() => setActiveTab('members')}
@@ -336,7 +339,7 @@ export default function AdminPage() {
                   : 'border-transparent text-gray-500 hover:text-gray-700'
               }`}
             >
-              Member Roles
+              {t('tabs.memberRoles')}
             </button>
             <button
               onClick={() => setActiveTab('relationships')}
@@ -346,7 +349,7 @@ export default function AdminPage() {
                   : 'border-transparent text-gray-500 hover:text-gray-700'
               }`}
             >
-              Relationship Types
+              {t('tabs.relationshipTypes')}
             </button>
           </nav>
         </div>
@@ -361,7 +364,7 @@ export default function AdminPage() {
           <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
             <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M15 19l-7-7 7-7" />
           </svg>
-          Back to Dashboard
+          {t('backToDashboard')}
         </button>
       </div>
 
@@ -370,7 +373,7 @@ export default function AdminPage() {
         {/* Project Settings Tab */}
         {activeTab === 'project' && (
           <div className="bg-white border border-gray-200 rounded-lg p-6">
-            <h2 className="text-xl font-semibold text-gray-800 mb-6">Project Settings</h2>
+            <h2 className="text-xl font-semibold text-gray-800 mb-6">{t('projectSettings.title')}</h2>
 
             <form onSubmit={handleProjectUpdate} className="space-y-6">
               {projectError && (
@@ -387,7 +390,7 @@ export default function AdminPage() {
 
               <div>
                 <label className="block text-sm font-medium text-gray-700 mb-1">
-                  Project Name <span className="text-red-500">*</span>
+                  {t('projectSettings.projectName')} <span className="text-red-500">*</span>
                 </label>
                 <input
                   type="text"
@@ -400,7 +403,7 @@ export default function AdminPage() {
 
               <div>
                 <label className="block text-sm font-medium text-gray-700 mb-1">
-                  Description
+                  {t('projectSettings.description')}
                 </label>
                 <textarea
                   value={projectDesc}
@@ -416,7 +419,7 @@ export default function AdminPage() {
                   disabled={projectLoading}
                   className="px-4 py-2 bg-teal-600 text-white rounded text-sm font-medium hover:bg-teal-700 disabled:opacity-50"
                 >
-                  {projectLoading ? 'Saving...' : 'Save Changes'}
+                  {projectLoading ? tCommon('saving') : t('projectSettings.saveButton')}
                 </button>
               </div>
             </form>
@@ -426,7 +429,7 @@ export default function AdminPage() {
         {/* Members Tab */}
         {activeTab === 'members' && (
           <div className="bg-white border border-gray-200 rounded-lg p-6">
-            <h2 className="text-xl font-semibold text-gray-800 mb-6">Member Roles</h2>
+            <h2 className="text-xl font-semibold text-gray-800 mb-6">{t('memberRoles.title')}</h2>
 
             {membersError && (
               <div className="mb-4 p-3 bg-red-100 border border-red-400 text-red-700 rounded text-sm">
@@ -435,17 +438,17 @@ export default function AdminPage() {
             )}
 
             {membersLoading ? (
-              <div className="text-center py-8 text-gray-500">Loading members...</div>
+              <div className="text-center py-8 text-gray-500">{t('memberRoles.loadingMembers')}</div>
             ) : members.length === 0 ? (
-              <div className="text-center py-8 text-gray-500">No members found</div>
+              <div className="text-center py-8 text-gray-500">{t('memberRoles.noMembers')}</div>
             ) : (
               <div className="overflow-x-auto">
                 <table className="w-full">
                   <thead>
                     <tr className="border-b border-gray-200">
-                      <th className="text-left py-3 px-4 font-medium text-gray-700">User</th>
-                      <th className="text-left py-3 px-4 font-medium text-gray-700">Role</th>
-                      <th className="text-left py-3 px-4 font-medium text-gray-700">Actions</th>
+                      <th className="text-left py-3 px-4 font-medium text-gray-700">{t('memberRoles.tableHeaders.user')}</th>
+                      <th className="text-left py-3 px-4 font-medium text-gray-700">{t('memberRoles.tableHeaders.role')}</th>
+                      <th className="text-left py-3 px-4 font-medium text-gray-700">{t('memberRoles.tableHeaders.actions')}</th>
                     </tr>
                   </thead>
                   <tbody>
@@ -459,7 +462,7 @@ export default function AdminPage() {
                               <span className="text-sm text-gray-900">{member.sub}</span>
                               {isCurrentUser && (
                                 <span className="text-xs bg-teal-100 text-teal-700 px-2 py-0.5 rounded">
-                                  You
+                                  {t('memberRoles.youBadge')}
                                 </span>
                               )}
                             </div>
@@ -485,7 +488,7 @@ export default function AdminPage() {
                               className={`px-3 py-1.5 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 ${
                                 isCurrentUser && member.role_id === 3 ? 'bg-gray-100 cursor-not-allowed' : ''
                               }`}
-                              title={isCurrentUser && member.role_id === 3 ? 'You cannot demote yourself' : ''}
+                              title={isCurrentUser && member.role_id === 3 ? t('memberRoles.cannotDemoteSelf') : ''}
                             >
                               {roles.map((role) => (
                                 <option key={role.id} value={role.id}>
@@ -494,7 +497,7 @@ export default function AdminPage() {
                               ))}
                             </select>
                             {updatingMember === member.id && (
-                              <span className="ml-2 text-xs text-gray-500">Saving...</span>
+                              <span className="ml-2 text-xs text-gray-500">{tCommon('saving')}</span>
                             )}
                           </td>
                         </tr>
@@ -511,7 +514,7 @@ export default function AdminPage() {
         {activeTab === 'relationships' && (
           <div className="bg-white border border-gray-200 rounded-lg p-6">
             <div className="flex items-center justify-between mb-6">
-              <h2 className="text-xl font-semibold text-gray-800">Relationship Types</h2>
+              <h2 className="text-xl font-semibold text-gray-800">{t('relationshipTypes.title')}</h2>
               <button
                 onClick={() => {
                   resetRelTypeForm()
@@ -519,7 +522,7 @@ export default function AdminPage() {
                 }}
                 className="px-4 py-2 bg-teal-600 text-white rounded text-sm font-medium hover:bg-teal-700"
               >
-                + Add Type
+                {t('relationshipTypes.addButton')}
               </button>
             </div>
 
@@ -530,10 +533,10 @@ export default function AdminPage() {
             )}
 
             {relTypesLoading ? (
-              <div className="text-center py-8 text-gray-500">Loading relationship types...</div>
+              <div className="text-center py-8 text-gray-500">{t('relationshipTypes.loadingTypes')}</div>
             ) : relationshipTypes.length === 0 ? (
               <div className="text-center py-8 text-gray-500">
-                No relationship types defined yet. Create one to link requirements.
+                {t('relationshipTypes.noTypes')}
               </div>
             ) : (
               <div className="space-y-3">
@@ -546,7 +549,7 @@ export default function AdminPage() {
                       <div className="font-medium text-gray-900">{relType.type_name}</div>
                       {relType.inverse_type_name && (
                         <div className="text-sm text-gray-500">
-                          Inverse: {relType.inverse_type_name}
+                          {t('relationshipTypes.inverse')} {relType.inverse_type_name}
                         </div>
                       )}
                       {relType.type_description && (
@@ -558,13 +561,13 @@ export default function AdminPage() {
                         onClick={() => openEditModal(relType)}
                         className="px-3 py-1.5 border border-gray-300 rounded text-sm text-gray-700 hover:bg-gray-100"
                       >
-                        Edit
+                        {t('relationshipTypes.editButton')}
                       </button>
                       <button
                         onClick={() => openDeleteModal(relType)}
                         className="px-3 py-1.5 border border-red-300 rounded text-sm text-red-600 hover:bg-red-50"
                       >
-                        Delete
+                        {t('relationshipTypes.deleteButton')}
                       </button>
                     </div>
                   </div>
@@ -580,7 +583,7 @@ export default function AdminPage() {
         <div className="fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center z-50">
           <div className="bg-white rounded-lg shadow-xl w-full max-w-md mx-4">
             <div className="flex items-center justify-between px-6 py-4 border-b border-gray-200">
-              <h2 className="text-xl font-semibold text-gray-800">Create Relationship Type</h2>
+              <h2 className="text-xl font-semibold text-gray-800">{t('createRelTypeModal.title')}</h2>
               <button
                 onClick={() => {
                   setShowCreateRelTypeModal(false)
@@ -604,13 +607,13 @@ export default function AdminPage() {
 
                 <div>
                   <label className="block text-sm font-medium text-gray-700 mb-1">
-                    Type Name <span className="text-red-500">*</span>
+                    {t('createRelTypeModal.typeName')} <span className="text-red-500">*</span>
                   </label>
                   <input
                     type="text"
                     value={relTypeName}
                     onChange={(e) => setRelTypeName(e.target.value)}
-                    placeholder="e.g., Depends On"
+                    placeholder={t('createRelTypeModal.typeNamePlaceholder')}
                     className="w-full px-3 py-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500"
                     required
                   />
@@ -618,23 +621,23 @@ export default function AdminPage() {
 
                 <div>
                   <label className="block text-sm font-medium text-gray-700 mb-1">
-                    Inverse Name
+                    {t('createRelTypeModal.inverseName')}
                   </label>
                   <input
                     type="text"
                     value={relTypeInverse}
                     onChange={(e) => setRelTypeInverse(e.target.value)}
-                    placeholder="e.g., Depended By"
+                    placeholder={t('createRelTypeModal.inverseNamePlaceholder')}
                     className="w-full px-3 py-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500"
                   />
                   <p className="text-xs text-gray-500 mt-1">
-                    Optional. The name shown when viewing from the target requirement.
+                    {t('createRelTypeModal.inverseNameHint')}
                   </p>
                 </div>
 
                 <div>
                   <label className="block text-sm font-medium text-gray-700 mb-1">
-                    Description
+                    {t('createRelTypeModal.description')}
                   </label>
                   <textarea
                     value={relTypeDesc}
@@ -655,14 +658,14 @@ export default function AdminPage() {
                   className="px-4 py-2 border border-gray-400 rounded text-sm font-medium text-gray-700 hover:bg-gray-100"
                   disabled={relTypeFormLoading}
                 >
-                  Cancel
+                  {tCommon('cancel')}
                 </button>
                 <button
                   type="submit"
                   className="px-4 py-2 bg-teal-600 text-white rounded text-sm font-medium hover:bg-teal-700 disabled:opacity-50"
                   disabled={relTypeFormLoading}
                 >
-                  {relTypeFormLoading ? 'Creating...' : 'Create'}
+                  {relTypeFormLoading ? tCommon('creating') : t('createRelTypeModal.createButton')}
                 </button>
               </div>
             </form>
@@ -675,7 +678,7 @@ export default function AdminPage() {
         <div className="fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center z-50">
           <div className="bg-white rounded-lg shadow-xl w-full max-w-md mx-4">
             <div className="flex items-center justify-between px-6 py-4 border-b border-gray-200">
-              <h2 className="text-xl font-semibold text-gray-800">Edit Relationship Type</h2>
+              <h2 className="text-xl font-semibold text-gray-800">{t('editRelTypeModal.title')}</h2>
               <button
                 onClick={() => {
                   setShowEditRelTypeModal(false)
@@ -700,7 +703,7 @@ export default function AdminPage() {
 
                 <div>
                   <label className="block text-sm font-medium text-gray-700 mb-1">
-                    Type Name <span className="text-red-500">*</span>
+                    {t('createRelTypeModal.typeName')} <span className="text-red-500">*</span>
                   </label>
                   <input
                     type="text"
@@ -713,7 +716,7 @@ export default function AdminPage() {
 
                 <div>
                   <label className="block text-sm font-medium text-gray-700 mb-1">
-                    Inverse Name
+                    {t('createRelTypeModal.inverseName')}
                   </label>
                   <input
                     type="text"
@@ -725,7 +728,7 @@ export default function AdminPage() {
 
                 <div>
                   <label className="block text-sm font-medium text-gray-700 mb-1">
-                    Description
+                    {t('createRelTypeModal.description')}
                   </label>
                   <textarea
                     value={relTypeDesc}
@@ -747,14 +750,14 @@ export default function AdminPage() {
                   className="px-4 py-2 border border-gray-400 rounded text-sm font-medium text-gray-700 hover:bg-gray-100"
                   disabled={relTypeFormLoading}
                 >
-                  Cancel
+                  {tCommon('cancel')}
                 </button>
                 <button
                   type="submit"
                   className="px-4 py-2 bg-teal-600 text-white rounded text-sm font-medium hover:bg-teal-700 disabled:opacity-50"
                   disabled={relTypeFormLoading}
                 >
-                  {relTypeFormLoading ? 'Saving...' : 'Save Changes'}
+                  {relTypeFormLoading ? tCommon('saving') : t('editRelTypeModal.saveButton')}
                 </button>
               </div>
             </form>
@@ -767,7 +770,7 @@ export default function AdminPage() {
         <div className="fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center z-50">
           <div className="bg-white rounded-lg shadow-xl w-full max-w-md mx-4">
             <div className="px-6 py-4 border-b border-gray-200">
-              <h2 className="text-xl font-semibold text-gray-800">Delete Relationship Type</h2>
+              <h2 className="text-xl font-semibold text-gray-800">{t('deleteRelTypeModal.title')}</h2>
             </div>
 
             <div className="px-6 py-4">
@@ -778,11 +781,11 @@ export default function AdminPage() {
               )}
 
               <p className="text-gray-700">
-                Are you sure you want to delete the relationship type{' '}
+                {t('deleteRelTypeModal.confirmMessage')}{' '}
                 <span className="font-semibold">"{selectedRelType.type_name}"</span>?
               </p>
               <p className="text-sm text-red-600 mt-2">
-                ⚠️ This will also delete all requirement links using this type.
+                {t('deleteRelTypeModal.warningMessage')}
               </p>
             </div>
 
@@ -796,14 +799,14 @@ export default function AdminPage() {
                 className="px-4 py-2 border border-gray-400 rounded text-sm font-medium text-gray-700 hover:bg-gray-100"
                 disabled={relTypeFormLoading}
               >
-                Cancel
+                {tCommon('cancel')}
               </button>
               <button
                 onClick={handleDeleteRelType}
                 className="px-4 py-2 bg-red-600 text-white rounded text-sm font-medium hover:bg-red-700 disabled:opacity-50"
                 disabled={relTypeFormLoading}
               >
-                {relTypeFormLoading ? 'Deleting...' : 'Delete'}
+                {relTypeFormLoading ? tCommon('deleting') : t('deleteRelTypeModal.deleteButton')}
               </button>
             </div>
           </div>

frontend/src/pages/DashboardPage.tsx

@@ -1,7 +1,9 @@
 import { useState, useEffect } from 'react'
+import { useTranslation } from 'react-i18next'
 import { useAuth, useProject } from '@/hooks'
 import { useNavigate } from 'react-router-dom'
 import { groupService, requirementService, Group } from '@/services'
+import { LanguageSelector } from '@/components'
 import type { Requirement } from '@/services/requirementService'
 
 /**
@@ -73,6 +75,8 @@ export default function DashboardPage() {
   const { user, logout } = useAuth()
   const { projects, currentProject, setCurrentProject, isLoading: projectsLoading, createProject } = useProject()
   const navigate = useNavigate()
+  const { t } = useTranslation('dashboard')
+  const { t: tCommon } = useTranslation('common')
   const [groups, setGroups] = useState<Group[]>([])
   const [requirements, setRequirements] = useState<Requirement[]>([])
   const [loading, setLoading] = useState(true)
@@ -235,9 +239,9 @@ export default function DashboardPage() {
         {/* Sidebar Header */}
         <div className="p-6 border-b border-slate-700">
           <h1 className="text-lg font-semibold text-teal-400">
-            Digital Twin
+            {t('sidebar.title')}
           </h1>
-          <p className="text-sm text-slate-400">Requirements Tool</p>
+          <p className="text-sm text-slate-400">{t('sidebar.subtitle')}</p>
         </div>
 
         {/* Navigation */}
@@ -250,11 +254,11 @@ export default function DashboardPage() {
             <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
               <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M12 4v16m8-8H4" />
             </svg>
-            Create Requirement
+            {t('sidebar.createRequirement')}
           </button>
 
           <div className="pt-4 pb-2">
-            <p className="px-4 text-xs font-semibold text-slate-500 uppercase tracking-wider">Navigation</p>
+            <p className="px-4 text-xs font-semibold text-slate-500 uppercase tracking-wider">{t('sidebar.navigation')}</p>
           </div>
 
           {/* Search Requirements */}
@@ -265,7 +269,7 @@ export default function DashboardPage() {
             <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
               <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M21 21l-6-6m2-5a7 7 0 11-14 0 7 7 0 0114 0z" />
             </svg>
-            Search Requirements
+            {t('sidebar.searchRequirements')}
           </button>
 
           {/* My Requirements */}
@@ -276,7 +280,7 @@ export default function DashboardPage() {
             <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
               <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 5H7a2 2 0 00-2 2v12a2 2 0 002 2h10a2 2 0 002-2V7a2 2 0 00-2-2h-2M9 5a2 2 0 002 2h2a2 2 0 002-2M9 5a2 2 0 012-2h2a2 2 0 012 2" />
             </svg>
-            My Requirements
+            {t('sidebar.myRequirements')}
           </button>
 
           {/* Reports */}
@@ -286,22 +290,22 @@ export default function DashboardPage() {
             <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
               <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 17v-2m3 2v-4m3 4v-6m2 10H7a2 2 0 01-2-2V5a2 2 0 012-2h5.586a1 1 0 01.707.293l5.414 5.414a1 1 0 01.293.707V19a2 2 0 01-2 2z" />
             </svg>
-            Generate Report
+            {t('sidebar.generateReport')}
           </button>
         </nav>
 
         {/* Project Stats Summary at bottom */}
         {currentProject && !loading && (
           <div className="absolute bottom-0 left-0 w-64 p-4 border-t border-slate-700 bg-slate-900">
-            <p className="text-xs font-semibold text-slate-500 uppercase tracking-wider mb-3">Project Summary</p>
+            <p className="text-xs font-semibold text-slate-500 uppercase tracking-wider mb-3">{t('sidebar.projectSummary')}</p>
             <div className="grid grid-cols-2 gap-2 text-center">
               <div className="bg-slate-800 rounded p-2">
                 <p className="text-xl font-bold text-white">{getTotalStats().total}</p>
-                <p className="text-xs text-slate-400">Total</p>
+                <p className="text-xs text-slate-400">{t('sidebar.total')}</p>
               </div>
               <div className="bg-slate-800 rounded p-2">
                 <p className="text-xl font-bold text-green-400">{getTotalStats().validated}</p>
-                <p className="text-xs text-slate-400">Validated</p>
+                <p className="text-xs text-slate-400">{t('sidebar.validated')}</p>
               </div>
             </div>
           </div>
@@ -315,7 +319,7 @@ export default function DashboardPage() {
           <div className="flex items-center justify-between">
             {/* Breadcrumb with Project Dropdown */}
             <div className="flex items-center gap-2">
-              <span className="text-sm text-gray-500">Projects</span>
+              <span className="text-sm text-gray-500">{t('header.projects')}</span>
               <svg className="w-4 h-4 text-gray-400" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                 <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 5l7 7-7 7" />
               </svg>
@@ -327,7 +331,7 @@ export default function DashboardPage() {
                   className="flex items-center gap-2 text-sm font-semibold text-gray-900 hover:text-teal-700 focus:outline-none"
                 >
                   {projectsLoading ? (
-                    <span className="text-gray-500">Loading...</span>
+                    <span className="text-gray-500">{tCommon('loading')}</span>
                   ) : currentProject ? (
                     <>
                       {currentProject.project_name}
@@ -336,7 +340,7 @@ export default function DashboardPage() {
                       </svg>
                     </>
                   ) : (
-                    <span className="text-gray-500 italic">No project selected</span>
+                    <span className="text-gray-500 italic">{t('projectDropdown.noProjectSelected')}</span>
                   )}
                 </button>
                 
@@ -346,7 +350,7 @@ export default function DashboardPage() {
                     <div className="py-1">
                       {projects.length === 0 ? (
                         <div className="px-4 py-2 text-sm text-gray-500">
-                          No projects available
+                          {t('projectDropdown.noProjectsAvailable')}
                         </div>
                       ) : (
                         projects.map((project) => (
@@ -376,7 +380,7 @@ export default function DashboardPage() {
                         }}
                         className="w-full text-left px-4 py-2 text-sm text-teal-600 hover:bg-gray-100 font-medium"
                       >
-                        + Create New Project
+                        {t('projectDropdown.createNewProject')}
                       </button>
                     </div>
                   </div>
@@ -386,14 +390,8 @@ export default function DashboardPage() {
 
             {/* Right side utilities - grouped tighter */}
             <div className="flex items-center gap-4">
-              {/* Language Toggle */}
-              <div className="flex items-center gap-2 text-sm text-gray-500">
-                <span>EN</span>
-                <div className="relative inline-flex h-5 w-9 items-center rounded-full bg-gray-300 cursor-pointer">
-                  <span className="inline-block h-3.5 w-3.5 transform rounded-full bg-white shadow-sm translate-x-0.5" />
-                </div>
-                <span>PT</span>
-              </div>
+              {/* Language Selector */}
+              <LanguageSelector compact />
 
               {/* Divider */}
               <div className="h-6 w-px bg-gray-300"></div>
@@ -408,7 +406,7 @@ export default function DashboardPage() {
                     <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M10.325 4.317c.426-1.756 2.924-1.756 3.35 0a1.724 1.724 0 002.573 1.066c1.543-.94 3.31.826 2.37 2.37a1.724 1.724 0 001.065 2.572c1.756.426 1.756 2.924 0 3.35a1.724 1.724 0 00-1.066 2.573c.94 1.543-.826 3.31-2.37 2.37a1.724 1.724 0 00-2.572 1.065c-.426 1.756-2.924 1.756-3.35 0a1.724 1.724 0 00-2.573-1.066c-1.543.94-3.31-.826-2.37-2.37a1.724 1.724 0 00-1.065-2.572c-1.756-.426-1.756-2.924 0-3.35a1.724 1.724 0 001.066-2.573c-.94-1.543.826-3.31 2.37-2.37.996.608 2.296.07 2.572-1.065z" />
                     <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M15 12a3 3 0 11-6 0 3 3 0 016 0z" />
                   </svg>
-                  Admin
+                  {t('header.admin')}
                 </button>
               )}
 
@@ -422,15 +420,15 @@ export default function DashboardPage() {
                   </div>
                   <div className="text-sm">
                     <p className="font-medium text-gray-700">
-                      {user?.full_name || user?.preferred_username || 'User'}
+                      {user?.full_name || user?.preferred_username || tCommon('user')}
                     </p>
-                    <p className="text-xs text-gray-500">{user?.role || 'user'}</p>
+                    <p className="text-xs text-gray-500">{user?.role || tCommon('user').toLowerCase()}</p>
                   </div>
                 </div>
                 <button
                   onClick={logout}
                   className="p-2 text-gray-400 hover:text-gray-600 hover:bg-gray-100 rounded-lg transition-colors"
-                  title="Logout"
+                  title={tCommon('logout')}
                 >
                   <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                     <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M17 16l4-4m0 0l-4-4m4 4H7m6 4v1a3 3 0 01-3 3H6a3 3 0 01-3-3V7a3 3 0 013-3h4a3 3 0 013 3v1" />
@@ -451,16 +449,16 @@ export default function DashboardPage() {
                   <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M12 9v2m0 4h.01m-6.938 4h13.856c1.54 0 2.502-1.667 1.732-3L13.732 4c-.77-1.333-2.694-1.333-3.464 0L3.34 16c-.77 1.333.192 3 1.732 3z" />
                 </svg>
                 <div>
-                  <h3 className="font-semibold text-amber-800">No Project Selected</h3>
+                  <h3 className="font-semibold text-amber-800">{t('noProjectWarning.title')}</h3>
                   <p className="text-sm text-amber-700">
-                    Please select a project from the dropdown above or{' '}
+                    {t('noProjectWarning.messagePart1')}{' '}
                     <button
                       onClick={() => setShowCreateProjectModal(true)}
                       className="underline font-medium hover:text-amber-900"
                     >
-                      create a new project
+                      {t('noProjectWarning.createProject')}
                     </button>
-                    {' '}to get started.
+                    {' '}{t('noProjectWarning.messagePart2')}
                   </p>
                 </div>
               </div>
@@ -471,10 +469,10 @@ export default function DashboardPage() {
           <div>
             <div className="flex items-center justify-between mb-6">
               <h2 className="text-xl font-semibold text-gray-800">
-                Quick Search Filters
+                {t('quickFilters.title')}
               </h2>
               <p className="text-sm text-gray-500">
-                Click a category to filter requirements
+                {t('quickFilters.subtitle')}
               </p>
             </div>
 
@@ -483,7 +481,7 @@ export default function DashboardPage() {
               <div className="flex justify-center items-center min-h-[200px]">
                 <div className="text-center">
                   <div className="animate-spin rounded-full h-10 w-10 border-b-2 border-teal-600 mx-auto"></div>
-                  <p className="mt-3 text-gray-500">Loading...</p>
+                  <p className="mt-3 text-gray-500">{tCommon('loading')}</p>
                 </div>
               </div>
             )}
@@ -556,7 +554,7 @@ export default function DashboardPage() {
                           <span 
                             className={`ml-auto text-xs ${isLightText ? 'text-white/70' : 'text-black/50'}`}
                           >
-                            {stats.total} total
+                            {stats.total} {t('quickFilters.total')}
                           </span>
                         </div>
                       )}
@@ -569,7 +567,7 @@ export default function DashboardPage() {
             {/* Empty State */}
             {!loading && !error && groups.length === 0 && (
               <div className="flex justify-center items-center min-h-[200px]">
-                <div className="text-gray-500">No groups found</div>
+                <div className="text-gray-500">{t('quickFilters.noGroupsFound')}</div>
               </div>
             )}
           </div>
@@ -586,10 +584,10 @@ export default function DashboardPage() {
                   </div>
                   <div>
                     <h2 className="text-lg font-semibold text-gray-800">
-                      Needs Attention
+                      {t('needsAttention.title')}
                     </h2>
                     <p className="text-sm text-gray-500">
-                      Requirements with denied or partial validation
+                      {t('needsAttention.subtitle')}
                     </p>
                   </div>
                 </div>
@@ -597,7 +595,7 @@ export default function DashboardPage() {
                   onClick={handleNeedsAttentionClick}
                   className="flex items-center gap-2 px-4 py-2 text-sm font-medium text-amber-700 bg-amber-50 hover:bg-amber-100 rounded-lg transition-colors"
                 >
-                  View All ({requirementsNeedingAttention.length})
+                  {t('needsAttention.viewAll')} ({requirementsNeedingAttention.length})
                   <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                     <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 5l7 7-7 7" />
                   </svg>
@@ -653,7 +651,7 @@ export default function DashboardPage() {
                     onClick={handleNeedsAttentionClick}
                     className="text-sm text-amber-600 hover:text-amber-700 font-medium"
                   >
-                    + {requirementsNeedingAttention.length - 6} more requirements need attention
+                    + {requirementsNeedingAttention.length - 6} {t('needsAttention.moreRequirements')}
                   </button>
                 </div>
               )}
@@ -672,10 +670,10 @@ export default function DashboardPage() {
                   </div>
                   <div>
                     <h2 className="text-lg font-semibold text-gray-800">
-                      Needs Revalidation
+                      {t('needsRevalidation.title')}
                     </h2>
                     <p className="text-sm text-gray-500">
-                      Requirements updated since last validation
+                      {t('needsRevalidation.subtitle')}
                     </p>
                   </div>
                 </div>
@@ -683,7 +681,7 @@ export default function DashboardPage() {
                   onClick={handleNeedsRevalidationClick}
                   className="flex items-center gap-2 px-4 py-2 text-sm font-medium text-blue-700 bg-blue-50 hover:bg-blue-100 rounded-lg transition-colors"
                 >
-                  View All ({requirementsNeedingRevalidation.length})
+                  {t('needsRevalidation.viewAll')} ({requirementsNeedingRevalidation.length})
                   <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                     <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 5l7 7-7 7" />
                   </svg>
@@ -706,7 +704,7 @@ export default function DashboardPage() {
                           {req.tag.tag_code}
                         </span>
                         <span className="text-xs font-medium px-2 py-0.5 rounded bg-blue-100 text-blue-700">
-                          {versionDiff} version{versionDiff > 1 ? 's' : ''} behind
+                          {versionDiff} {versionDiff > 1 ? t('needsRevalidation.versionsBehind') : t('needsRevalidation.versionBehind')}
                         </span>
                       </div>
                       <h4 className="font-medium text-gray-800 text-sm line-clamp-2 mb-2">
@@ -717,8 +715,8 @@ export default function DashboardPage() {
                           v{req.validation_version} → v{req.version}
                         </span>
                         {req.validated_by && (
-                          <span className="truncate max-w-[120px]" title={`Last validated by ${req.validated_by}`}>
-                            by {req.validated_by}
+                          <span className="truncate max-w-[120px]" title={`${t('needsRevalidation.lastValidatedBy')} ${req.validated_by}`}>
+                            {t('needsRevalidation.by')} {req.validated_by}
                           </span>
                         )}
                       </div>
@@ -734,7 +732,7 @@ export default function DashboardPage() {
                     onClick={handleNeedsRevalidationClick}
                     className="text-sm text-blue-600 hover:text-blue-700 font-medium"
                   >
-                    + {requirementsNeedingRevalidation.length - 6} more requirements need revalidation
+                    + {requirementsNeedingRevalidation.length - 6} {t('needsRevalidation.moreRequirements')}
                   </button>
                 </div>
               )}
@@ -751,9 +749,9 @@ export default function DashboardPage() {
                   </svg>
                 </div>
                 <div>
-                  <h3 className="font-semibold text-green-800">All Clear!</h3>
+                  <h3 className="font-semibold text-green-800">{t('allClear.title')}</h3>
                   <p className="text-sm text-green-600">
-                    No requirements need attention. All validations are either approved or pending review.
+                    {t('allClear.message')}
                   </p>
                 </div>
               </div>
@@ -776,7 +774,7 @@ export default function DashboardPage() {
           <div className="bg-white rounded-lg shadow-xl w-full max-w-md mx-4">
             {/* Modal Header */}
             <div className="flex items-center justify-between px-6 py-4 border-b border-gray-200">
-              <h2 className="text-xl font-semibold text-gray-800">Create New Project</h2>
+              <h2 className="text-xl font-semibold text-gray-800">{t('createProject.title')}</h2>
               <button
                 onClick={() => {
                   setShowCreateProjectModal(false)
@@ -805,13 +803,13 @@ export default function DashboardPage() {
                 {/* Project Name */}
                 <div>
                   <label className="block text-sm font-medium text-gray-700 mb-1">
-                    Project Name <span className="text-red-500">*</span>
+                    {t('createProject.projectName')} <span className="text-red-500">*</span>
                   </label>
                   <input
                     type="text"
                     value={newProjectName}
                     onChange={(e) => setNewProjectName(e.target.value)}
-                    placeholder="Enter project name"
+                    placeholder={t('createProject.projectNamePlaceholder')}
                     className="w-full px-3 py-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 focus:border-transparent"
                     required
                   />
@@ -820,12 +818,12 @@ export default function DashboardPage() {
                 {/* Project Description */}
                 <div>
                   <label className="block text-sm font-medium text-gray-700 mb-1">
-                    Description
+                    {t('createProject.description')}
                   </label>
                   <textarea
                     value={newProjectDesc}
                     onChange={(e) => setNewProjectDesc(e.target.value)}
-                    placeholder="Enter project description (optional)"
+                    placeholder={t('createProject.descriptionPlaceholder')}
                     rows={3}
                     className="w-full px-3 py-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 focus:border-transparent resize-none"
                   />
@@ -845,14 +843,14 @@ export default function DashboardPage() {
                   className="px-4 py-2 border border-gray-400 rounded text-sm font-medium text-gray-700 hover:bg-gray-100"
                   disabled={createProjectLoading}
                 >
-                  Cancel
+                  {tCommon('cancel')}
                 </button>
                 <button
                   type="submit"
                   className="px-4 py-2 bg-teal-600 text-white rounded text-sm font-medium hover:bg-teal-700 disabled:opacity-50 disabled:cursor-not-allowed"
                   disabled={createProjectLoading}
                 >
-                  {createProjectLoading ? 'Creating...' : 'Create Project'}
+                  {createProjectLoading ? t('createProject.creating') : t('createProject.createButton')}
                 </button>
               </div>
             </form>
@@ -862,4 +860,3 @@ export default function DashboardPage() {
     </div>
   )
 }
-

frontend/src/pages/HomePage.tsx

@@ -1,7 +1,10 @@
+import { useTranslation } from 'react-i18next'
 import { useAuth } from '@/hooks'
 
 export default function HomePage() {
   const { isAuthenticated, login, isLoading } = useAuth()
+  const { t: tHome } = useTranslation('home')
+  const { t: tNavbar } = useTranslation('navbar')
 
   if (isLoading) {
     return (
@@ -32,10 +35,10 @@ export default function HomePage() {
         </div>
 
         <h1 className="text-4xl font-bold tracking-tight text-gray-900 sm:text-5xl">
-          Requirements Periodic Table
+          {tHome('title')}
         </h1>
         <p className="mx-auto mt-4 max-w-md text-lg text-gray-600">
-          Manage and track your project requirements.
+          {tHome('subtitle')}
         </p>
 
         <div className="mt-8">
@@ -57,14 +60,14 @@ export default function HomePage() {
                   d="M11 16l-4-4m0 0l4-4m-4 4h14m-5 4v1a3 3 0 01-3 3H6a3 3 0 01-3-3V7a3 3 0 013-3h7a3 3 0 013 3v1"
                 />
               </svg>
-              Login
+              {tNavbar('login')}
             </button>
           ) : (
             <a
               href="/dashboard"
               className="inline-flex items-center gap-2 rounded-lg bg-primary-600 px-8 py-3 text-lg font-semibold text-white shadow-lg transition-all hover:bg-primary-700 hover:shadow-xl focus:outline-none focus:ring-4 focus:ring-primary-300"
             >
-              Go to Dashboard
+              {tHome('goToDashboard')}
             </a>
           )}
         </div>

frontend/src/pages/RequirementDetailPage.tsx

@@ -1,4 +1,5 @@
 import { useState, useEffect } from 'react'
+import { useTranslation } from 'react-i18next'
 import { useAuth, useProject } from '@/hooks'
 import { useParams, Link } from 'react-router-dom'
 import { requirementService, validationService, relationshipService, commentService, tagService, priorityService, groupService, requirementStatusService } from '@/services'
@@ -40,6 +41,8 @@ interface TimelineEvent {
 }
 
 export default function RequirementDetailPage() {
+  const { t } = useTranslation('requirementDetail')
+  const { t: tCommon } = useTranslation('common')
   const { user, logout, isAuditor } = useAuth()
   const { currentProject } = useProject()
   const { id } = useParams<{ id: string }>()
@@ -719,7 +722,7 @@ export default function RequirementDetailPage() {
       <div className="min-h-screen bg-white flex items-center justify-center">
         <div className="text-center">
           <div className="animate-spin rounded-full h-12 w-12 border-b-2 border-teal-600 mx-auto"></div>
-          <p className="mt-4 text-gray-600">Loading requirement...</p>
+          <p className="mt-4 text-gray-600">{t('loadingRequirement')}</p>
         </div>
       </div>
     )
@@ -730,10 +733,10 @@ export default function RequirementDetailPage() {
       <div className="min-h-screen bg-white flex items-center justify-center">
         <div className="text-center">
           <h2 className="text-2xl font-semibold text-gray-700 mb-4">
-            {error || 'Requirement not found'}
+            {error || t('requirementNotFound')}
           </h2>
           <Link to="/requirements" className="text-teal-600 hover:underline">
-            Back to Requirements
+            {t('backToRequirements')}
           </Link>
         </div>
       </div>
@@ -741,12 +744,12 @@ export default function RequirementDetailPage() {
   }
 
   const tabs: { id: TabType; label: string }[] = [
-    { id: 'description', label: 'Description' },
-    { id: 'relationships', label: 'Relationships' },
-    { id: 'acceptance-criteria', label: 'Acceptance Criteria' },
-    { id: 'shared-comments', label: 'Shared Comments' },
-    { id: 'validate', label: 'Validate' },
-    { id: 'history', label: 'History' },
+    { id: 'description', label: t('tabs.description') },
+    { id: 'relationships', label: t('tabs.relationships') },
+    { id: 'acceptance-criteria', label: t('tabs.acceptanceCriteria') },
+    { id: 'shared-comments', label: t('tabs.sharedComments') },
+    { id: 'validate', label: t('tabs.validate') },
+    { id: 'history', label: t('tabs.history') },
   ]
 
   // Get display values from the requirement data
@@ -759,7 +762,7 @@ export default function RequirementDetailPage() {
       case 'description':
         return (
           <div>
-            <h3 className="text-xl font-bold text-gray-800 mb-2">Description</h3>
+            <h3 className="text-xl font-bold text-gray-800 mb-2">{t('description.title')}</h3>
             
             {/* Draft indicator banner */}
             {isDraftStatus && (
@@ -767,18 +770,18 @@ export default function RequirementDetailPage() {
                 <div className="flex items-center gap-2">
                   <span className="text-amber-600 text-lg">📝</span>
                   <div>
-                    <p className="font-semibold text-amber-800">Draft Requirement</p>
-                    <p className="text-sm text-amber-700">This requirement is still in draft status and is not finalized. It may be subject to changes.</p>
+                    <p className="font-semibold text-amber-800">{t('draft.title')}</p>
+                    <p className="text-sm text-amber-700">{t('draft.message')}</p>
                   </div>
                 </div>
               </div>
             )}
             
             <p className="text-sm text-gray-700 mb-2">
-              <span className="font-semibold">Version:</span> {requirement.version}
+              <span className="font-semibold">{t('description.version')}</span> {requirement.version}
             </p>
             <p className="text-sm text-gray-700 mb-2">
-              <span className="font-semibold">Status:</span>{' '}
+              <span className="font-semibold">{t('description.status')}</span>{' '}
               <span className={`inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium ${
                 isDraftStatus 
                   ? 'bg-amber-100 text-amber-800 border border-amber-300' 
@@ -788,7 +791,7 @@ export default function RequirementDetailPage() {
               </span>
             </p>
             <p className="text-sm text-gray-700 mb-2">
-              <span className="font-semibold">Validation Status:</span>{' '}
+              <span className="font-semibold">{t('description.validationStatus')}</span>{' '}
               <span className={`inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium ${getValidationStatusStyle(validationStatus)}`}>
                 {validationStatus}
               </span>
@@ -802,7 +805,7 @@ export default function RequirementDetailPage() {
               )}
             </p>
             <p className="text-sm text-gray-700 mb-2">
-              <span className="font-semibold">Author:</span>{' '}
+              <span className="font-semibold">{t('description.author')}</span>{' '}
               {requirement.author_username ? (
                 <span className="text-gray-700">{requirement.author_username}</span>
               ) : (
@@ -811,22 +814,22 @@ export default function RequirementDetailPage() {
             </p>
             {requirement.last_editor_username && (
               <p className="text-sm text-gray-700 mb-2">
-                <span className="font-semibold">Last Edited By:</span>{' '}
+                <span className="font-semibold">{t('description.lastEditedBy')}</span>{' '}
                 <span className="text-gray-700">{requirement.last_editor_username}</span>
               </p>
             )}
             {requirement.created_at && (
               <p className="text-sm text-gray-700 mb-2">
-                <span className="font-semibold">Created:</span> {new Date(requirement.created_at).toLocaleDateString()}
+                <span className="font-semibold">{t('description.created')}</span> {new Date(requirement.created_at).toLocaleDateString()}
               </p>
             )}
             {requirement.updated_at && (
               <p className="text-sm text-gray-700 mb-4">
-                <span className="font-semibold">Last Updated:</span> {new Date(requirement.updated_at).toLocaleDateString()}
+                <span className="font-semibold">{t('description.lastUpdated')}</span> {new Date(requirement.updated_at).toLocaleDateString()}
               </p>
             )}
             <div className="bg-teal-50 border border-gray-300 rounded min-h-[300px] p-4">
-              <p className="text-gray-700">{requirement.req_desc || 'No description provided.'}</p>
+              <p className="text-gray-700">{requirement.req_desc || t('description.noDescription')}</p>
             </div>
             {/* Hide Edit button for auditors */}
             {!isAuditor && (
@@ -835,7 +838,7 @@ export default function RequirementDetailPage() {
                   onClick={openEditModal}
                   className="px-4 py-1.5 border border-gray-400 rounded text-sm text-gray-700 hover:bg-gray-50"
                 >
-                  Edit
+                  {t('description.editButton')}
                 </button>
               </div>
             )}
@@ -846,43 +849,43 @@ export default function RequirementDetailPage() {
         return (
           <div>
             <div className="flex items-center justify-between mb-4">
-              <h3 className="text-xl font-bold text-gray-800">Relationships</h3>
+              <h3 className="text-xl font-bold text-gray-800">{t('relationships.title')}</h3>
               {!isAuditor && (
                 <button
                   onClick={openAddRelationshipModal}
                   disabled={relationshipTypes.length === 0}
                   className="px-4 py-1.5 bg-teal-600 text-white rounded text-sm font-medium hover:bg-teal-700 disabled:opacity-50 disabled:cursor-not-allowed"
-                  title={relationshipTypes.length === 0 ? 'No relationship types defined for this project. Contact an admin to set them up.' : ''}
+                  title={relationshipTypes.length === 0 ? t('relationships.noTypesWarning') : ''}
                 >
-                  Add Relationship
+                  {t('relationships.addButton')}
                 </button>
               )}
             </div>
 
             {relationshipTypes.length === 0 && !relationshipsLoading && (
               <div className="mb-4 p-3 bg-yellow-50 border border-yellow-200 rounded text-sm text-yellow-800">
-                No relationship types have been defined for this project. Contact an administrator to set up relationship types.
+                {t('relationships.noTypesWarning')}
               </div>
             )}
 
             {relationshipsLoading ? (
               <div className="text-center py-8">
                 <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-teal-600 mx-auto"></div>
-                <p className="mt-2 text-gray-500 text-sm">Loading relationships...</p>
+                <p className="mt-2 text-gray-500 text-sm">{t('relationships.loadingRelationships')}</p>
               </div>
             ) : relationshipLinks.length === 0 ? (
-              <p className="text-gray-500 text-center py-8">No relationships defined yet.</p>
+              <p className="text-gray-500 text-center py-8">{t('relationships.noRelationships')}</p>
             ) : (
               <div className="overflow-x-auto">
                 <table className="w-full border border-gray-200 rounded">
                   <thead className="bg-gray-50">
                     <tr>
-                      <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Direction</th>
-                      <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Type</th>
-                      <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Linked Requirement</th>
-                      <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Created By</th>
-                      <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Date</th>
-                      <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Actions</th>
+                      <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{t('relationships.tableHeaders.direction')}</th>
+                      <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{t('relationships.tableHeaders.type')}</th>
+                      <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{t('relationships.tableHeaders.linkedRequirement')}</th>
+                      <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{t('relationships.tableHeaders.createdBy')}</th>
+                      <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{t('relationships.tableHeaders.date')}</th>
+                      <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{t('relationships.tableHeaders.actions')}</th>
                     </tr>
                   </thead>
                   <tbody className="bg-white divide-y divide-gray-200">
@@ -894,7 +897,7 @@ export default function RequirementDetailPage() {
                               ? 'bg-blue-100 text-blue-800' 
                               : 'bg-purple-100 text-purple-800'
                           }`}>
-                            {link.direction === 'outgoing' ? '→ Outgoing' : '← Incoming'}
+                            {link.direction === 'outgoing' ? t('relationships.outgoing') : t('relationships.incoming')}
                           </span>
                         </td>
                         <td className="px-4 py-3 text-sm text-gray-700">
@@ -944,12 +947,12 @@ export default function RequirementDetailPage() {
       case 'acceptance-criteria':
         return (
           <div>
-            <h3 className="text-xl font-bold text-gray-800 mb-4">Acceptance Criteria</h3>
-            <p className="text-gray-500">No acceptance criteria defined yet.</p>
+            <h3 className="text-xl font-bold text-gray-800 mb-4">{t('acceptanceCriteria.title')}</h3>
+            <p className="text-gray-500">{t('acceptanceCriteria.noCriteria')}</p>
             {!isAuditor && (
               <div className="mt-4">
                 <button className="px-4 py-1.5 border border-gray-400 rounded text-sm text-gray-700 hover:bg-gray-50">
-                  Add Criterion
+                  {t('acceptanceCriteria.addButton')}
                 </button>
               </div>
             )}
@@ -959,14 +962,14 @@ export default function RequirementDetailPage() {
       case 'shared-comments':
         return (
           <div>
-            <h3 className="text-xl font-bold text-gray-800 mb-4">Shared Comments</h3>
+            <h3 className="text-xl font-bold text-gray-800 mb-4">{t('comments.title')}</h3>
             
             {/* New Comment Form */}
             <div className="mb-6 p-4 border border-gray-200 rounded bg-gray-50">
               <textarea
                 value={newCommentText}
                 onChange={(e) => setNewCommentText(e.target.value)}
-                placeholder="Add a comment..."
+                placeholder={t('comments.placeholder')}
                 className="w-full p-3 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 resize-none"
                 rows={3}
                 disabled={postingComment}
@@ -977,7 +980,7 @@ export default function RequirementDetailPage() {
                   disabled={postingComment || !newCommentText.trim()}
                   className="px-4 py-1.5 bg-teal-600 text-white rounded text-sm font-medium hover:bg-teal-700 disabled:opacity-50 disabled:cursor-not-allowed"
                 >
-                  {postingComment ? 'Posting...' : 'Post Comment'}
+                  {postingComment ? t('comments.posting') : t('comments.postButton')}
                 </button>
               </div>
             </div>
@@ -986,10 +989,10 @@ export default function RequirementDetailPage() {
             {commentsLoading ? (
               <div className="text-center py-8">
                 <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-teal-600 mx-auto"></div>
-                <p className="mt-2 text-gray-500 text-sm">Loading comments...</p>
+                <p className="mt-2 text-gray-500 text-sm">{t('comments.loadingComments')}</p>
               </div>
             ) : comments.length === 0 ? (
-              <p className="text-gray-500 text-center py-8">No comments yet. Be the first to comment!</p>
+              <p className="text-gray-500 text-center py-8">{t('comments.noComments')}</p>
             ) : (
               <div className="space-y-4">
                 {comments.map((comment) => (
@@ -1038,7 +1041,7 @@ export default function RequirementDetailPage() {
                         }}
                         className="mt-2 text-xs text-teal-600 hover:text-teal-700 font-medium"
                       >
-                        {replyingToCommentId === comment.id ? 'Cancel Reply' : 'Reply'}
+                        {replyingToCommentId === comment.id ? t('comments.cancelReply') : t('comments.reply')}
                       </button>
                       
                       {/* Reply Form */}
@@ -1047,7 +1050,7 @@ export default function RequirementDetailPage() {
                           <textarea
                             value={replyText}
                             onChange={(e) => setReplyText(e.target.value)}
-                            placeholder="Write a reply..."
+                            placeholder={t('comments.replyPlaceholder')}
                             className="w-full p-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 resize-none"
                             rows={2}
                             disabled={postingReply}
@@ -1058,7 +1061,7 @@ export default function RequirementDetailPage() {
                               disabled={postingReply || !replyText.trim()}
                               className="px-3 py-1 bg-teal-600 text-white rounded text-xs font-medium hover:bg-teal-700 disabled:opacity-50"
                             >
-                              {postingReply ? 'Posting...' : 'Post Reply'}
+                              {postingReply ? t('comments.posting') : t('comments.postReply')}
                             </button>
                           </div>
                         </div>
@@ -1117,25 +1120,25 @@ export default function RequirementDetailPage() {
       case 'validate':
         return (
           <div>
-            <h3 className="text-xl font-bold text-gray-800 mb-4">Validate Requirement</h3>
+            <h3 className="text-xl font-bold text-gray-800 mb-4">{t('validate.title')}</h3>
             
             {/* Current Status */}
             <div className="mb-6 p-4 bg-gray-50 border border-gray-200 rounded">
               <div className="flex items-center justify-between">
                 <div>
-                  <p className="text-sm text-gray-600">Current Status:</p>
+                  <p className="text-sm text-gray-600">{t('validate.currentStatus')}</p>
                   <span className={`inline-flex items-center px-3 py-1 rounded-full text-sm font-medium ${getValidationStatusStyle(validationStatus)}`}>
                     {validationStatus}
                   </span>
                 </div>
                 <div className="text-right">
-                  <p className="text-sm text-gray-600">Requirement Version:</p>
+                  <p className="text-sm text-gray-600">{t('validate.requirementVersion')}</p>
                   <span className="text-lg font-semibold text-gray-800">{requirement.version}</span>
                 </div>
               </div>
               {requirement.validated_by && (
                 <p className="text-sm text-gray-500 mt-2">
-                  Last validated by {requirement.validated_by}
+                  {t('validate.lastValidatedBy')} {requirement.validated_by}
                   {requirement.validated_at && ` on ${new Date(requirement.validated_at).toLocaleDateString()}`}
                 </p>
               )}
@@ -1144,7 +1147,7 @@ export default function RequirementDetailPage() {
                   <p className="text-sm text-orange-800 flex items-center gap-2">
                     <span>⚠️</span>
                     <span>
-                      This requirement was modified after the last validation (validated at version {requirement.validation_version}, current version {requirement.version}).
+                      {t('validate.staleWarning', { validationVersion: requirement.validation_version, currentVersion: requirement.version })}
                     </span>
                   </p>
                 </div>
@@ -1154,7 +1157,7 @@ export default function RequirementDetailPage() {
             {/* Validation Form - Only for auditors */}
             {isAuditor && (
               <div className="mb-6 p-4 border border-gray-300 rounded">
-                <h4 className="font-semibold text-gray-800 mb-4">Submit Validation</h4>
+                <h4 className="font-semibold text-gray-800 mb-4">{t('validate.submitTitle')}</h4>
                 
                 {validationError && (
                   <div className="mb-4 p-3 bg-red-100 border border-red-400 text-red-700 rounded text-sm">
@@ -1166,7 +1169,7 @@ export default function RequirementDetailPage() {
                   {/* Status Selection */}
                   <div>
                     <label className="block text-sm font-medium text-gray-700 mb-1">
-                      Validation Status <span className="text-red-500">*</span>
+                      {t('validate.statusLabel')} <span className="text-red-500">*</span>
                     </label>
                     <select
                       value={selectedStatusId}
@@ -1174,7 +1177,7 @@ export default function RequirementDetailPage() {
                       className="w-full px-3 py-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 focus:border-transparent"
                       disabled={validationLoading}
                     >
-                      <option value="">Select a status...</option>
+                      <option value="">{t('validate.selectStatus')}</option>
                       {validationStatuses.map((status) => (
                         <option key={status.id} value={status.id}>
                           {status.status_name}
@@ -1186,12 +1189,12 @@ export default function RequirementDetailPage() {
                   {/* Comment */}
                   <div>
                     <label className="block text-sm font-medium text-gray-700 mb-1">
-                      Comment
+                      {t('validate.commentLabel')}
                     </label>
                     <textarea
                       value={validationComment}
                       onChange={(e) => setValidationComment(e.target.value)}
-                      placeholder="Add a comment explaining your decision (optional but recommended)"
+                      placeholder={t('validate.commentPlaceholder')}
                       rows={4}
                       className="w-full p-3 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 resize-none"
                       disabled={validationLoading}
@@ -1204,7 +1207,7 @@ export default function RequirementDetailPage() {
                     disabled={validationLoading || !selectedStatusId}
                     className="px-4 py-2 bg-teal-600 text-white rounded text-sm font-medium hover:bg-teal-700 disabled:opacity-50 disabled:cursor-not-allowed"
                   >
-                    {validationLoading ? 'Submitting...' : 'Submit Validation'}
+                    {validationLoading ? t('validate.submitting') : t('validate.submitButton')}
                   </button>
                 </div>
               </div>
@@ -1212,25 +1215,25 @@ export default function RequirementDetailPage() {
 
             {/* Validation History */}
             <div>
-              <h4 className="font-semibold text-gray-800 mb-4">Validation History</h4>
+              <h4 className="font-semibold text-gray-800 mb-4">{t('validate.historyTitle')}</h4>
               
               {historyLoading ? (
                 <div className="text-center py-8">
                   <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-teal-600 mx-auto"></div>
-                  <p className="mt-2 text-gray-500 text-sm">Loading history...</p>
+                  <p className="mt-2 text-gray-500 text-sm">{t('validate.loadingHistory')}</p>
                 </div>
               ) : validationHistory.length === 0 ? (
-                <p className="text-gray-500 text-center py-8">No validation history yet.</p>
+                <p className="text-gray-500 text-center py-8">{t('validate.noHistory')}</p>
               ) : (
                 <div className="overflow-x-auto">
                   <table className="w-full border border-gray-200 rounded">
                     <thead className="bg-gray-50">
                       <tr>
-                        <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Date</th>
-                        <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Status</th>
-                        <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Version</th>
-                        <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Validator</th>
-                        <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Comment</th>
+                        <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{t('validate.tableHeaders.date')}</th>
+                        <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{t('validate.tableHeaders.status')}</th>
+                        <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{t('validate.tableHeaders.version')}</th>
+                        <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{t('validate.tableHeaders.validator')}</th>
+                        <th className="px-4 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{t('validate.tableHeaders.comment')}</th>
                       </tr>
                     </thead>
                     <tbody className="bg-white divide-y divide-gray-200">
@@ -1252,7 +1255,7 @@ export default function RequirementDetailPage() {
                               <span className="flex items-center gap-1">
                                 v{validation.req_version_snapshot}
                                 {isStale && (
-                                  <span className="text-orange-600" title="Requirement was modified after this validation">
+                                  <span className="text-orange-600" title={t('validate.staleWarning', { validationVersion: validation.req_version_snapshot, currentVersion: requirement.version })}>
                                     ⚠️
                                   </span>
                                 )}
@@ -1262,7 +1265,7 @@ export default function RequirementDetailPage() {
                               {validation.validator_username}
                             </td>
                             <td className="px-4 py-3 text-sm text-gray-700">
-                              {validation.comment || <span className="text-gray-400 italic">No comment</span>}
+                              {validation.comment || <span className="text-gray-400 italic">{t('validate.noComment')}</span>}
                             </td>
                           </tr>
                         )
@@ -1290,11 +1293,11 @@ export default function RequirementDetailPage() {
         
         return (
           <div>
-            <h3 className="text-xl font-bold text-gray-800 mb-4">Version History</h3>
+            <h3 className="text-xl font-bold text-gray-800 mb-4">{t('history.title')}</h3>
             
             {/* Author info */}
             <div className="mb-4 p-3 bg-gray-50 border border-gray-200 rounded text-sm">
-              <span className="font-medium text-gray-700">Original Author:</span>{' '}
+              <span className="font-medium text-gray-700">{t('history.originalAuthor')}</span>{' '}
               {requirement.author_username ? (
                 <span className="text-gray-800">{requirement.author_username}</span>
               ) : (
@@ -1310,10 +1313,10 @@ export default function RequirementDetailPage() {
             {reqHistoryLoading ? (
               <div className="text-center py-8">
                 <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-teal-600 mx-auto"></div>
-                <p className="mt-2 text-gray-500 text-sm">Loading history...</p>
+                <p className="mt-2 text-gray-500 text-sm">{t('history.loadingHistory')}</p>
               </div>
             ) : timelineEvents.length === 0 ? (
-              <p className="text-gray-500 text-center py-8">No history yet. History is recorded when the requirement is edited or relationships change.</p>
+              <p className="text-gray-500 text-center py-8">{t('history.noHistory')}</p>
             ) : (
               <div className="space-y-3">
                 {timelineEvents.map((event) => {
@@ -1346,7 +1349,7 @@ export default function RequirementDetailPage() {
                             <span className="font-semibold text-gray-800">
                               v{oldItem.version} → v{newItem ? newItem.version : requirement.version}
                             </span>
-                            <span className="text-sm text-gray-600">Requirement edited</span>
+                            <span className="text-sm text-gray-600">{t('history.requirementEdited')}</span>
                           </div>
                           <div className="flex items-center gap-4 text-sm text-gray-500">
                             {oldItem.edited_by_username && (
@@ -1365,7 +1368,7 @@ export default function RequirementDetailPage() {
                         {isExpanded && (
                           <div className="px-4 py-3 border-t border-gray-200 bg-white space-y-4">
                             {!hasAnyChange && (
-                              <p className="text-gray-500 italic text-sm">No visible changes detected (may be a group-only change).</p>
+                              <p className="text-gray-500 italic text-sm">{t('history.noChangesDetected')}</p>
                             )}
                             
                             {/* Name diff */}
@@ -1463,7 +1466,7 @@ export default function RequirementDetailPage() {
                                     }}
                                     className="mt-2 text-sm text-teal-600 hover:underline"
                                   >
-                                    {showFullDescDiff === event.id ? 'Show less' : 'Show full diff'}
+                                    {showFullDescDiff === event.id ? t('history.showLess') : t('history.showFullDiff')}
                                   </button>
                                 )}
                               </div>
@@ -1481,7 +1484,7 @@ export default function RequirementDetailPage() {
                         <div className="flex items-center justify-between px-4 py-3 bg-green-50 border-l-4 border-green-400">
                           <div className="flex items-center gap-3">
                             <span className="text-green-600 text-lg">🔗</span>
-                            <span className="font-medium text-gray-800">Link Created</span>
+                            <span className="font-medium text-gray-800">{t('history.linkCreated')}</span>
                             <span className="text-sm text-gray-600">
                               {link.isSource ? (
                                 <>
@@ -1528,7 +1531,7 @@ export default function RequirementDetailPage() {
                         <div className="flex items-center justify-between px-4 py-3 bg-red-50 border-l-4 border-red-400">
                           <div className="flex items-center gap-3">
                             <span className="text-red-600 text-lg">🔗</span>
-                            <span className="font-medium text-gray-800">Link Removed</span>
+                            <span className="font-medium text-gray-800">{t('history.linkRemoved')}</span>
                             <span className="text-sm text-gray-600">
                               {link.isSource ? (
                                 <>
@@ -1572,7 +1575,7 @@ export default function RequirementDetailPage() {
                         <div className="flex items-center justify-between px-4 py-3 bg-green-50 border-l-4 border-green-400">
                           <div className="flex items-center gap-3">
                             <span className="text-green-600 text-lg">🏷️</span>
-                            <span className="font-medium text-gray-800">Group Added</span>
+                            <span className="font-medium text-gray-800">{t('history.groupAdded')}</span>
                             <span className="text-sm text-gray-600">
                               {group.groupName ? (
                                 <span 
@@ -1606,7 +1609,7 @@ export default function RequirementDetailPage() {
                         <div className="flex items-center justify-between px-4 py-3 bg-orange-50 border-l-4 border-orange-400">
                           <div className="flex items-center gap-3">
                             <span className="text-orange-600 text-lg">🏷️</span>
-                            <span className="font-medium text-gray-800">Group Removed</span>
+                            <span className="font-medium text-gray-800">{t('history.groupRemoved')}</span>
                             <span className="text-sm text-gray-600">
                               {group.groupName ? (
                                 <span 
@@ -1650,7 +1653,7 @@ export default function RequirementDetailPage() {
       {/* Header */}
       <header className="py-6 text-center">
         <h1 className="text-3xl font-semibold text-teal-700">
-          Digital Twin Requirements Tool
+          {t('pageTitle')}
         </h1>
       </header>
 
@@ -1659,22 +1662,13 @@ export default function RequirementDetailPage() {
         <div className="flex items-center justify-between max-w-7xl mx-auto">
           {/* Breadcrumb */}
           <div className="text-sm">
-            <Link to="/dashboard" className="text-gray-600 hover:underline">Projects</Link>
+            <Link to="/dashboard" className="text-gray-600 hover:underline">{tCommon('projects')}</Link>
             <span className="mx-2 text-gray-400">»</span>
-            <Link to="/dashboard" className="text-gray-600 hover:underline">{currentProject?.project_name || 'Project'}</Link>
+            <Link to="/dashboard" className="text-gray-600 hover:underline">{currentProject?.project_name || tCommon('project')}</Link>
             <span className="mx-2 text-gray-400">»</span>
-            <Link to="/requirements" className="text-gray-600 hover:underline">Search</Link>
+            <Link to="/requirements" className="text-gray-600 hover:underline">{t('breadcrumb.search')}</Link>
             <span className="mx-2 text-gray-400">»</span>
-            <span className="font-semibold text-gray-900">Details {tagCode}</span>
-          </div>
-
-          {/* Language Toggle */}
-          <div className="flex items-center gap-2 text-sm text-gray-600">
-            <span>English</span>
-            <div className="relative inline-flex h-5 w-10 items-center rounded-full bg-gray-300">
-              <span className="inline-block h-4 w-4 transform rounded-full bg-white shadow-sm translate-x-0.5" />
-            </div>
-            <span>Portuguese</span>
+            <span className="font-semibold text-gray-900">{t('breadcrumb.details')} {tagCode}</span>
           </div>
 
           {/* User Info */}
@@ -1684,15 +1678,15 @@ export default function RequirementDetailPage() {
                 <path fillRule="evenodd" d="M10 9a3 3 0 100-6 3 3 0 000 6zm-7 9a7 7 0 1114 0H3z" clipRule="evenodd" />
               </svg>
               <span className="text-sm text-gray-700">
-                {user?.full_name || user?.preferred_username || 'User'}{' '}
-                <span className="text-gray-500">({user?.role || 'user'})</span>
+                {user?.full_name || user?.preferred_username || tCommon('user')}{' '}
+                <span className="text-gray-500">({user?.role || tCommon('user')})</span>
               </span>
             </div>
             <button
               onClick={logout}
               className="px-3 py-1 border border-gray-400 rounded text-sm text-gray-700 hover:bg-gray-50"
             >
-              Logout
+              {tCommon('logout')}
             </button>
           </div>
         </div>
@@ -1706,7 +1700,7 @@ export default function RequirementDetailPage() {
           {isDraftStatus && (
             <div className="mb-4 inline-flex items-center gap-2 px-4 py-2 bg-amber-100 border-2 border-dashed border-amber-400 rounded-lg">
               <span className="text-amber-600 text-lg">📝</span>
-              <span className="text-amber-800 font-medium">Draft - Not Finalized</span>
+              <span className="text-amber-800 font-medium">{t('draft.badge')}</span>
             </div>
           )}
           
@@ -1788,7 +1782,7 @@ export default function RequirementDetailPage() {
           <div className="bg-white rounded-lg shadow-xl w-full max-w-lg mx-4">
             {/* Modal Header */}
             <div className="flex items-center justify-between px-6 py-4 border-b border-gray-200">
-              <h2 className="text-xl font-semibold text-gray-800">Add Relationship</h2>
+              <h2 className="text-xl font-semibold text-gray-800">{t('addRelationshipModal.title')}</h2>
               <button
                 onClick={closeAddRelationshipModal}
                 className="text-gray-400 hover:text-gray-600"
@@ -1808,7 +1802,7 @@ export default function RequirementDetailPage() {
               {/* Relationship Type Selection */}
               <div>
                 <label className="block text-sm font-medium text-gray-700 mb-1">
-                  Relationship Type <span className="text-red-500">*</span>
+                  {t('addRelationshipModal.relationshipType')} <span className="text-red-500">*</span>
                 </label>
                 <select
                   value={selectedRelationshipType}
@@ -1816,7 +1810,7 @@ export default function RequirementDetailPage() {
                   className="w-full px-3 py-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 focus:border-transparent"
                   disabled={addLinkLoading}
                 >
-                  <option value="">Select a relationship type...</option>
+                  <option value="">{t('addRelationshipModal.selectType')}</option>
                   {relationshipTypes.map((type) => (
                     <option key={type.id} value={type.id}>
                       {type.type_name}
@@ -1829,7 +1823,7 @@ export default function RequirementDetailPage() {
               {/* Target Requirement Search */}
               <div>
                 <label className="block text-sm font-medium text-gray-700 mb-1">
-                  Target Requirement <span className="text-red-500">*</span>
+                  {t('addRelationshipModal.targetRequirement')} <span className="text-red-500">*</span>
                 </label>
                 <div className="relative">
                   <input
@@ -1839,7 +1833,7 @@ export default function RequirementDetailPage() {
                       setTargetSearchQuery(e.target.value)
                       setSelectedTarget(null)
                     }}
-                    placeholder="Search by tag code or name..."
+                    placeholder={t('addRelationshipModal.searchPlaceholder')}
                     className="w-full px-3 py-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 focus:border-transparent"
                     disabled={addLinkLoading}
                   />
@@ -1868,7 +1862,7 @@ export default function RequirementDetailPage() {
                 </div>
                 {selectedTarget && (
                   <p className="mt-1 text-sm text-green-600">
-                    ✓ Selected: {selectedTarget.tag_code} - {selectedTarget.req_name}
+                    ✓ {t('addRelationshipModal.selected')} {selectedTarget.tag_code} - {selectedTarget.req_name}
                   </p>
                 )}
               </div>
@@ -1882,7 +1876,7 @@ export default function RequirementDetailPage() {
                 className="px-4 py-2 border border-gray-300 rounded text-sm text-gray-700 hover:bg-gray-100"
                 disabled={addLinkLoading}
               >
-                Cancel
+                {tCommon('cancel')}
               </button>
               <button
                 type="button"
@@ -1890,7 +1884,7 @@ export default function RequirementDetailPage() {
                 disabled={addLinkLoading || !selectedRelationshipType || !selectedTarget}
                 className="px-4 py-2 bg-teal-600 text-white rounded text-sm font-medium hover:bg-teal-700 disabled:opacity-50 disabled:cursor-not-allowed"
               >
-                {addLinkLoading ? 'Creating...' : 'Create Relationship'}
+                {addLinkLoading ? tCommon('creating') : t('addRelationshipModal.createButton')}
               </button>
             </div>
           </div>
@@ -1903,7 +1897,7 @@ export default function RequirementDetailPage() {
           <div className="bg-white rounded-lg shadow-xl w-full max-w-2xl mx-4 max-h-[90vh] overflow-hidden flex flex-col">
             {/* Modal Header */}
             <div className="flex items-center justify-between px-6 py-4 border-b border-gray-200">
-              <h2 className="text-xl font-semibold text-gray-800">Edit Requirement</h2>
+              <h2 className="text-xl font-semibold text-gray-800">{t('editModal.title')}</h2>
               <button
                 onClick={closeEditModal}
                 className="text-gray-400 hover:text-gray-600"
@@ -1923,14 +1917,14 @@ export default function RequirementDetailPage() {
               {editOptionsLoading ? (
                 <div className="text-center py-8">
                   <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-teal-600 mx-auto"></div>
-                  <p className="mt-2 text-gray-500 text-sm">Loading options...</p>
+                  <p className="mt-2 text-gray-500 text-sm">{t('editModal.loadingOptions')}</p>
                 </div>
               ) : (
                 <>
                   {/* Name */}
                   <div>
                     <label className="block text-sm font-medium text-gray-700 mb-1">
-                      Name <span className="text-red-500">*</span>
+                      {t('editModal.name')} <span className="text-red-500">*</span>
                     </label>
                     <input
                       type="text"
@@ -1944,7 +1938,7 @@ export default function RequirementDetailPage() {
                   {/* Tag */}
                   <div>
                     <label className="block text-sm font-medium text-gray-700 mb-1">
-                      Tag <span className="text-red-500">*</span>
+                      {t('editModal.tag')} <span className="text-red-500">*</span>
                     </label>
                     <select
                       value={editTagId}
@@ -1952,7 +1946,7 @@ export default function RequirementDetailPage() {
                       className="w-full px-3 py-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 focus:border-transparent"
                       disabled={editLoading}
                     >
-                      <option value="">Select a tag...</option>
+                      <option value="">{t('editModal.selectTag')}</option>
                       {availableTags.map((tag) => (
                         <option key={tag.id} value={tag.id}>
                           {tag.tag_code} - {tag.tag_description}
@@ -1964,7 +1958,7 @@ export default function RequirementDetailPage() {
                   {/* Priority */}
                   <div>
                     <label className="block text-sm font-medium text-gray-700 mb-1">
-                      Priority
+                      {t('editModal.priority')}
                     </label>
                     <select
                       value={editPriorityId}
@@ -1972,7 +1966,7 @@ export default function RequirementDetailPage() {
                       className="w-full px-3 py-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 focus:border-transparent"
                       disabled={editLoading}
                     >
-                      <option value="">No priority</option>
+                      <option value="">{t('editModal.noPriority')}</option>
                       {availablePriorities.map((priority) => (
                         <option key={priority.id} value={priority.id}>
                           {priority.priority_name}
@@ -1984,7 +1978,7 @@ export default function RequirementDetailPage() {
                   {/* Status */}
                   <div>
                     <label className="block text-sm font-medium text-gray-700 mb-1">
-                      Status
+                      {t('editModal.status')}
                     </label>
                     <select
                       value={editStatusId}
@@ -1999,14 +1993,14 @@ export default function RequirementDetailPage() {
                       ))}
                     </select>
                     <p className="mt-1 text-xs text-gray-500">
-                      Draft requirements are not finalized and marked with a visual indicator.
+                      {t('editModal.draftNote')}
                     </p>
                   </div>
 
                   {/* Description */}
                   <div>
                     <label className="block text-sm font-medium text-gray-700 mb-1">
-                      Description
+                      {t('editModal.description')}
                     </label>
                     <textarea
                       value={editReqDesc}
@@ -2020,10 +2014,10 @@ export default function RequirementDetailPage() {
                   {/* Groups */}
                   <div>
                     <label className="block text-sm font-medium text-gray-700 mb-2">
-                      Groups
+                      {t('editModal.groups')}
                     </label>
                     {availableGroups.length === 0 ? (
-                      <p className="text-sm text-gray-500 italic">No groups available</p>
+                      <p className="text-sm text-gray-500 italic">{t('editModal.noGroupsAvailable')}</p>
                     ) : (
                       <div className="grid grid-cols-2 gap-2 max-h-40 overflow-y-auto border border-gray-200 rounded p-3">
                         {availableGroups.map((group) => (
@@ -2064,7 +2058,7 @@ export default function RequirementDetailPage() {
                 className="px-4 py-2 border border-gray-300 rounded text-sm text-gray-700 hover:bg-gray-100"
                 disabled={editLoading}
               >
-                Cancel
+                {tCommon('cancel')}
               </button>
               <button
                 type="button"
@@ -2072,7 +2066,7 @@ export default function RequirementDetailPage() {
                 disabled={editLoading || editOptionsLoading || !editReqName.trim() || !editTagId}
                 className="px-4 py-2 bg-teal-600 text-white rounded text-sm font-medium hover:bg-teal-700 disabled:opacity-50 disabled:cursor-not-allowed"
               >
-                {editLoading ? 'Saving...' : 'Save Changes'}
+                {editLoading ? tCommon('saving') : tCommon('saveChanges')}
               </button>
             </div>
           </div>
@@ -2114,14 +2108,14 @@ export default function RequirementDetailPage() {
                 className="px-4 py-2 border border-gray-400 rounded text-sm font-medium text-gray-700 hover:bg-gray-100"
                 disabled={deleteConfirmLoading}
               >
-                Cancel
+                {tCommon('cancel')}
               </button>
               <button
                 onClick={handleConfirmDelete}
                 className="px-4 py-2 bg-red-600 text-white rounded text-sm font-medium hover:bg-red-700 disabled:opacity-50 disabled:cursor-not-allowed"
                 disabled={deleteConfirmLoading}
               >
-                {deleteConfirmLoading ? 'Deleting...' : 'Delete'}
+                {deleteConfirmLoading ? tCommon('deleting') : tCommon('delete')}
               </button>
             </div>
           </div>

frontend/src/pages/RequirementsPage.tsx

@@ -1,7 +1,9 @@
 import React, { useState, useEffect } from 'react'
+import { useTranslation } from 'react-i18next'
 import { useAuth, useProject } from '@/hooks'
 import { useSearchParams, Link, useNavigate, useLocation } from 'react-router-dom'
 import { groupService, tagService, requirementService, priorityService } from '@/services'
+import { LanguageSelector } from '@/components'
 import type { Group } from '@/services/groupService'
 import type { Tag } from '@/services/tagService'
 import type { Priority } from '@/services/priorityService'
@@ -30,6 +32,8 @@ const isDraftStatus = (statusCode: string | undefined): boolean => {
 }
 
 export default function RequirementsPage() {
+  const { t } = useTranslation('requirements')
+  const { t: tCommon } = useTranslation('common')
   const { user, logout, isAuditor } = useAuth()
   const { currentProject, isLoading: projectLoading } = useProject()
   const [searchParams, setSearchParams] = useSearchParams()
@@ -366,7 +370,7 @@ export default function RequirementsPage() {
       <div className="min-h-screen bg-white flex items-center justify-center">
         <div className="text-center">
           <div className="animate-spin rounded-full h-12 w-12 border-b-2 border-teal-600 mx-auto"></div>
-          <p className="mt-4 text-gray-600">Loading requirements...</p>
+          <p className="mt-4 text-gray-600">{t('loadingRequirements')}</p>
         </div>
       </div>
     )
@@ -379,13 +383,13 @@ export default function RequirementsPage() {
           <svg className="w-16 h-16 text-gray-400 mx-auto mb-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
             <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M3 7v10a2 2 0 002 2h14a2 2 0 002-2V9a2 2 0 00-2-2h-6l-2-2H5a2 2 0 00-2 2z" />
           </svg>
-          <h2 className="text-xl font-semibold text-gray-700 mb-2">No Project Selected</h2>
-          <p className="text-gray-500 mb-4">Please select a project from the dashboard to view requirements.</p>
+          <h2 className="text-xl font-semibold text-gray-700 mb-2">{t('noProjectSelected.title')}</h2>
+          <p className="text-gray-500 mb-4">{t('noProjectSelected.message')}</p>
           <button
             onClick={() => navigate('/dashboard')}
             className="px-4 py-2 bg-teal-600 text-white rounded hover:bg-teal-700"
           >
-            Go to Dashboard
+            {t('noProjectSelected.goToDashboard')}
           </button>
         </div>
       </div>
@@ -401,7 +405,7 @@ export default function RequirementsPage() {
             onClick={() => window.location.reload()}
             className="px-4 py-2 bg-teal-600 text-white rounded hover:bg-teal-700"
           >
-            Retry
+            {tCommon('retry')}
           </button>
         </div>
       </div>
@@ -413,7 +417,7 @@ export default function RequirementsPage() {
       {/* Header */}
       <header className="py-6 text-center">
         <h1 className="text-3xl font-semibold text-teal-700">
-          Digital Twin Requirements Tool
+          {t('header.title')}
         </h1>
       </header>
 
@@ -422,21 +426,15 @@ export default function RequirementsPage() {
         <div className="flex items-center justify-between max-w-7xl mx-auto">
           {/* Breadcrumb */}
           <div className="text-sm">
-            <Link to="/dashboard" className="text-gray-600 hover:underline">Projects</Link>
+            <Link to="/dashboard" className="text-gray-600 hover:underline">{t('breadcrumb.projects')}</Link>
             <span className="mx-2 text-gray-400">»</span>
             <Link to="/dashboard" className="text-gray-600 hover:underline">{currentProject.project_name}</Link>
             <span className="mx-2 text-gray-400">»</span>
-            <span className="font-semibold text-gray-900">Search Requirements</span>
+            <span className="font-semibold text-gray-900">{t('breadcrumb.searchRequirements')}</span>
           </div>
 
-          {/* Language Toggle */}
-          <div className="flex items-center gap-2 text-sm text-gray-600">
-            <span>English</span>
-            <div className="relative inline-flex h-5 w-10 items-center rounded-full bg-gray-300">
-              <span className="inline-block h-4 w-4 transform rounded-full bg-white shadow-sm translate-x-0.5" />
-            </div>
-            <span>Portuguese</span>
-          </div>
+          {/* Language Selector */}
+          <LanguageSelector compact />
 
           {/* User Info */}
           <div className="flex items-center gap-3">
@@ -445,15 +443,15 @@ export default function RequirementsPage() {
                 <path fillRule="evenodd" d="M10 9a3 3 0 100-6 3 3 0 000 6zm-7 9a7 7 0 1114 0H3z" clipRule="evenodd" />
               </svg>
               <span className="text-sm text-gray-700">
-                {user?.full_name || user?.preferred_username || 'User'}{' '}
-                <span className="text-gray-500">({user?.role || 'user'})</span>
+                {user?.full_name || user?.preferred_username || tCommon('user')}{' '}
+                <span className="text-gray-500">({user?.role || tCommon('user').toLowerCase()})</span>
               </span>
             </div>
             <button
               onClick={logout}
               className="px-3 py-1 border border-gray-400 rounded text-sm text-gray-700 hover:bg-gray-50"
             >
-              Logout
+              {tCommon('logout')}
             </button>
           </div>
         </div>
@@ -470,7 +468,7 @@ export default function RequirementsPage() {
                   onClick={openCreateModal}
                   className="px-4 py-2 border border-gray-400 rounded text-sm font-medium text-gray-700 hover:bg-gray-50"
                 >
-                  New Requirement
+                  {t('newRequirement')}
                 </button>
                 <button 
                   onClick={toggleDeletedPanel}
@@ -483,7 +481,7 @@ export default function RequirementsPage() {
                   <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                     <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M19 7l-.867 12.142A2 2 0 0116.138 21H7.862a2 2 0 01-1.995-1.858L5 7m5 4v6m4-6v6m1-10V4a1 1 0 00-1-1h-4a1 1 0 00-1 1v3M4 7h16" />
                   </svg>
-                  Deleted
+                  {t('deleted')}
                   {deletedRequirements.length > 0 && (
                     <span className="bg-red-500 text-white text-xs px-1.5 py-0.5 rounded-full">
                       {deletedRequirements.length}
@@ -505,7 +503,7 @@ export default function RequirementsPage() {
                   <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                     <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M19 7l-.867 12.142A2 2 0 0116.138 21H7.862a2 2 0 01-1.995-1.858L5 7m5 4v6m4-6v6m1-10V4a1 1 0 00-1-1h-4a1 1 0 00-1 1v3M4 7h16" />
                   </svg>
-                  Deleted
+                  {t('deleted')}
                   {deletedRequirements.length > 0 && (
                     <span className="bg-red-500 text-white text-xs px-1.5 py-0.5 rounded-full">
                       {deletedRequirements.length}
@@ -519,7 +517,7 @@ export default function RequirementsPage() {
             <div className="flex gap-2 mb-6">
               <input
                 type="text"
-                placeholder="Search for a requirement tag or title"
+                placeholder={t('searchPlaceholder')}
                 value={searchQuery}
                 onChange={(e) => setSearchQuery(e.target.value)}
                 className="flex-1 px-4 py-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 focus:border-transparent"
@@ -528,19 +526,19 @@ export default function RequirementsPage() {
                 onClick={handleSearch}
                 className="px-4 py-2 border border-gray-400 rounded text-sm font-medium text-gray-700 hover:bg-gray-50"
               >
-                Search
+                {tCommon('search')}
               </button>
               <button 
                 onClick={handleClear}
                 className="px-4 py-2 border border-gray-400 rounded text-sm font-medium text-gray-700 hover:bg-gray-50"
               >
-                Clear
+                {tCommon('clear')}
               </button>
             </div>
 
             {/* Filter Group */}
             <div className="mb-6">
-              <p className="text-sm text-gray-600 mb-3">Filter Group</p>
+              <p className="text-sm text-gray-600 mb-3">{t('filters.filterGroup')}</p>
               <div className="grid grid-cols-3 gap-x-8 gap-y-2">
                 {groups.map((group) => (
                   <label key={group.id} className="flex items-center gap-2 cursor-pointer">
@@ -559,16 +557,16 @@ export default function RequirementsPage() {
             {/* Filter Validation Status */}
             <div className="mb-6">
               <div className="flex items-center justify-between mb-3">
-                <p className="text-sm text-gray-600">Filter Validation Status</p>
+                <p className="text-sm text-gray-600">{t('filters.filterValidationStatus')}</p>
                 <div className="flex items-center gap-2">
                   {needsRevalidationFilter && (
                     <span className="text-xs bg-blue-100 text-blue-700 px-2 py-1 rounded-full">
-                      Showing: Needs Revalidation
+                      {t('filters.showingNeedsRevalidation')}
                     </span>
                   )}
                   {selectedValidationStatuses.includes('__NEEDS_ATTENTION__') && (
                     <span className="text-xs bg-amber-100 text-amber-700 px-2 py-1 rounded-full">
-                      Showing: Needs Attention
+                      {t('filters.showingNeedsAttention')}
                     </span>
                   )}
                 </div>
@@ -587,7 +585,7 @@ export default function RequirementsPage() {
                     <svg className="w-3.5 h-3.5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                       <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M4 4v5h.582m15.356 2A8.001 8.001 0 004.582 9m0 0H9m11 11v-5h-.581m0 0a8.003 8.003 0 01-15.357-2m15.357 2H15" />
                     </svg>
-                    Needs Revalidation
+                    {t('filters.needsRevalidation')}
                   </button>
                 )}
                 {['Approved', 'Denied', 'Partially Approved', 'Not Validated'].map((status) => {
@@ -602,6 +600,12 @@ export default function RequirementsPage() {
                     'Partially Approved': isSelected ? 'bg-yellow-100 border-yellow-500 text-yellow-800' : 'bg-white border-gray-300 text-gray-600 hover:border-yellow-400',
                     'Not Validated': isSelected ? 'bg-gray-200 border-gray-500 text-gray-800' : 'bg-white border-gray-300 text-gray-600 hover:border-gray-400',
                   }
+                  const statusTranslations: Record<string, string> = {
+                    'Approved': t('filters.statuses.approved'),
+                    'Denied': t('filters.statuses.denied'),
+                    'Partially Approved': t('filters.statuses.partiallyApproved'),
+                    'Not Validated': t('filters.statuses.notValidated'),
+                  }
                   return (
                     <button
                       key={status}
@@ -615,7 +619,7 @@ export default function RequirementsPage() {
                       }}
                       className={`px-3 py-1.5 rounded-full text-sm font-medium border-2 transition-colors ${statusStyles[status]}`}
                     >
-                      {status}
+                      {statusTranslations[status]}
                     </button>
                   )
                 })}
@@ -625,18 +629,18 @@ export default function RequirementsPage() {
             {/* Order By */}
             <div className="flex items-center justify-between mb-6">
               <div className="flex items-center gap-2">
-                <span className="text-sm text-gray-600">Order by:</span>
+                <span className="text-sm text-gray-600">{t('orderBy.label')}:</span>
                 <select
                   value={orderBy}
                   onChange={(e) => setOrderBy(e.target.value as 'Date' | 'Priority' | 'Name')}
                   className="px-3 py-1 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500"
                 >
-                  <option value="Date">Date</option>
-                  <option value="Priority">Priority</option>
-                  <option value="Name">Name</option>
+                  <option value="Date">{t('orderBy.date')}</option>
+                  <option value="Priority">{t('orderBy.priority')}</option>
+                  <option value="Name">{t('orderBy.name')}</option>
                 </select>
                 <button className="px-4 py-1 border border-gray-400 rounded text-sm font-medium text-gray-700 hover:bg-gray-50">
-                  Filter
+                  {tCommon('filter')}
                 </button>
               </div>
               
@@ -644,12 +648,12 @@ export default function RequirementsPage() {
               <button
                 onClick={() => setShowCaptionModal(true)}
                 className="flex items-center gap-2 px-3 py-1.5 border border-teal-500 rounded text-sm font-medium text-teal-700 hover:bg-teal-50 transition-colors"
-                title="View tag captions"
+                title={t('caption.viewCaptions')}
               >
                 <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                   <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z" />
                 </svg>
-                Caption
+                {t('caption.title')}
               </button>
             </div>
 
@@ -678,9 +682,9 @@ export default function RequirementsPage() {
                         {isDraft && (
                           <span 
                             className="inline-flex items-center px-2 py-0.5 rounded text-xs font-medium bg-amber-100 text-amber-800 border border-amber-300 flex-shrink-0"
-                            title="This requirement is still in draft and not finalized"
+                            title={t('requirement.draftTooltip')}
                           >
-                            📝 Draft
+                            📝 {t('requirement.draft')}
                           </span>
                         )}
                         <span 
@@ -711,13 +715,13 @@ export default function RequirementsPage() {
                                 className="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-gray-100 text-gray-600"
                                 title={req.groups.slice(2).map(g => g.group_name).join(', ')}
                               >
-                                +{req.groups.length - 2} more
+                                +{req.groups.length - 2} {t('requirement.more')}
                               </span>
                             )}
                           </>
                         ) : (
                           <span className="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-gray-100 text-gray-500">
-                            No groups
+                            {t('requirement.noGroups')}
                           </span>
                         )}
                       </div>
@@ -730,22 +734,22 @@ export default function RequirementsPage() {
                           {validationStatus}
                         </span>
                         {isStale && (
-                          <span className="inline-flex items-center px-2 py-0.5 rounded-full text-xs font-medium bg-orange-100 text-orange-800" title="Requirement was modified after validation">
-                            ⚠ Stale
+                          <span className="inline-flex items-center px-2 py-0.5 rounded-full text-xs font-medium bg-orange-100 text-orange-800" title={t('requirement.staleTooltip')}>
+                            ⚠ {t('requirement.stale')}
                           </span>
                         )}
                       </div>
                       {req.validated_by && (
                         <p className="text-xs text-gray-500 mt-1 text-center truncate" title={req.validated_by}>
-                          by {req.validated_by}
+                          {t('requirement.by')} {req.validated_by}
                         </p>
                       )}
                     </div>
                     
                     {/* Priority and Version */}
                     <div className="w-[120px] lg:w-[140px] flex-shrink-0 px-3 py-3">
-                      <p className="text-sm text-gray-700 whitespace-nowrap">Priority: {priorityName}</p>
-                      <p className="text-sm text-gray-600">Version: {req.version}</p>
+                      <p className="text-sm text-gray-700 whitespace-nowrap">{t('requirement.priority')}: {priorityName}</p>
+                      <p className="text-sm text-gray-600">{t('requirement.version')}: {req.version}</p>
                     </div>
                     
                     {/* Spacer to push buttons to the right */}
@@ -757,14 +761,14 @@ export default function RequirementsPage() {
                         onClick={() => handleDetails(req.id)}
                         className="px-3 py-1.5 border border-gray-400 rounded text-sm text-gray-700 hover:bg-gray-50 whitespace-nowrap"
                       >
-                        Details
+                        {tCommon('details')}
                       </button>
                       {!isAuditor && (
                         <button
                           onClick={() => openDeleteModal(req.id, req.req_name)}
                           className="px-3 py-1.5 border border-gray-400 rounded text-sm text-gray-700 hover:bg-gray-50 whitespace-nowrap"
                         >
-                          Remove
+                          {tCommon('remove')}
                         </button>
                       )}
                     </div>
@@ -774,7 +778,7 @@ export default function RequirementsPage() {
 
               {sortedRequirements.length === 0 && (
                 <div className="text-center py-12 text-gray-500">
-                  No requirements found matching your criteria.
+                  {t('noRequirementsFound')}
                 </div>
               )}
             </div>
@@ -790,7 +794,7 @@ export default function RequirementsPage() {
               <svg className="w-5 h-5 text-red-600" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                 <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M19 7l-.867 12.142A2 2 0 0116.138 21H7.862a2 2 0 01-1.995-1.858L5 7m5 4v6m4-6v6m1-10V4a1 1 0 00-1-1h-4a1 1 0 00-1 1v3M4 7h16" />
               </svg>
-              <h2 className="text-lg font-semibold text-gray-800">Deleted Requirements</h2>
+              <h2 className="text-lg font-semibold text-gray-800">{t('deletedPanel.title')}</h2>
             </div>
             <button
               onClick={() => setShowDeletedPanel(false)}
@@ -813,8 +817,8 @@ export default function RequirementsPage() {
                 <svg className="w-12 h-12 text-gray-300 mx-auto mb-3" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                   <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 12l2 2 4-4m6 2a9 9 0 11-18 0 9 9 0 0118 0z" />
                 </svg>
-                <p>No deleted requirements found.</p>
-                <p className="text-sm mt-1">Deleted requirements will appear here.</p>
+                <p>{t('deletedPanel.noDeleted')}</p>
+                <p className="text-sm mt-1">{t('deletedPanel.deletedWillAppear')}</p>
               </div>
             ) : (
               <div className="space-y-3">
@@ -834,7 +838,7 @@ export default function RequirementsPage() {
                           </span>
                         </div>
                         <h4 className="font-medium text-gray-800 truncate">
-                          {req.req_name || 'Unnamed Requirement'}
+                          {req.req_name || t('deletedPanel.unnamed')}
                         </h4>
                         {req.req_desc && (
                           <p className="text-sm text-gray-500 mt-1 line-clamp-2">
@@ -847,17 +851,17 @@ export default function RequirementsPage() {
                     <div className="mt-3 pt-3 border-t border-gray-200 text-xs text-gray-500 space-y-1">
                       {req.priority_name && (
                         <p>
-                          <span className="text-gray-400">Priority:</span>{' '}
+                          <span className="text-gray-400">{t('requirement.priority')}:</span>{' '}
                           <span className="font-medium">{req.priority_name}</span>
                         </p>
                       )}
                       <p>
-                        <span className="text-gray-400">Original ID:</span>{' '}
+                        <span className="text-gray-400">{t('deletedPanel.originalId')}:</span>{' '}
                         <span className="font-medium">#{req.original_req_id}</span>
                       </p>
                       {req.deleted_at && (
                         <p>
-                          <span className="text-gray-400">Deleted:</span>{' '}
+                          <span className="text-gray-400">{t('deletedPanel.deletedAt')}:</span>{' '}
                           <span className="font-medium">
                             {new Date(req.deleted_at).toLocaleDateString('en-US', {
                               year: 'numeric',
@@ -884,7 +888,7 @@ export default function RequirementsPage() {
 
           {/* Panel Footer */}
           <div className="px-6 py-3 border-t border-gray-200 bg-gray-50 text-xs text-gray-500">
-            <p>💡 Deleted requirements are preserved in history for auditing purposes.</p>
+            <p>💡 {t('deletedPanel.footerNote')}</p>
           </div>
         </div>
       )}
@@ -907,7 +911,7 @@ export default function RequirementsPage() {
                 <svg className="w-5 h-5 text-red-600" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                   <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M19 7l-.867 12.142A2 2 0 0116.138 21H7.862a2 2 0 01-1.995-1.858L5 7m5 4v6m4-6v6m1-10V4a1 1 0 00-1-1h-4a1 1 0 00-1 1v3M4 7h16" />
                 </svg>
-                <h2 className="text-lg font-semibold text-gray-800">Delete Requirement</h2>
+                <h2 className="text-lg font-semibold text-gray-800">{t('deleteModal.title')}</h2>
               </div>
               <button
                 onClick={closeDeleteModal}
@@ -923,11 +927,11 @@ export default function RequirementsPage() {
             {/* Modal Body */}
             <div className="px-6 py-6">
               <p className="text-gray-700">
-                Are you sure you want to delete the requirement{' '}
+                {t('deleteModal.confirmMessage')}{' '}
                 <span className="font-semibold text-gray-900">"{deleteTarget.name}"</span>?
               </p>
               <p className="text-sm text-gray-500 mt-2">
-                This action will move the requirement to the deleted items. You can view deleted requirements from the "Deleted" panel.
+                {t('deleteModal.explanation')}
               </p>
             </div>
 
@@ -938,14 +942,14 @@ export default function RequirementsPage() {
                 className="px-4 py-2 border border-gray-400 rounded text-sm font-medium text-gray-700 hover:bg-gray-100"
                 disabled={deleteLoading}
               >
-                Cancel
+                {tCommon('cancel')}
               </button>
               <button
                 onClick={handleConfirmDelete}
                 className="px-4 py-2 bg-red-600 text-white rounded text-sm font-medium hover:bg-red-700 disabled:opacity-50 disabled:cursor-not-allowed"
                 disabled={deleteLoading}
               >
-                {deleteLoading ? 'Deleting...' : 'Delete'}
+                {deleteLoading ? t('deleteModal.deleting') : tCommon('delete')}
               </button>
             </div>
           </div>
@@ -962,7 +966,7 @@ export default function RequirementsPage() {
                 <svg className="w-5 h-5 text-teal-600" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                   <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z" />
                 </svg>
-                <h2 className="text-lg font-semibold text-gray-800">Tag Caption</h2>
+                <h2 className="text-lg font-semibold text-gray-800">{t('caption.title')}</h2>
               </div>
               <button
                 onClick={() => setShowCaptionModal(false)}
@@ -992,7 +996,7 @@ export default function RequirementsPage() {
                 onClick={() => setShowCaptionModal(false)}
                 className="px-4 py-2 bg-teal-600 text-white rounded text-sm font-medium hover:bg-teal-700"
               >
-                Close
+                {tCommon('close')}
               </button>
             </div>
           </div>
@@ -1005,7 +1009,7 @@ export default function RequirementsPage() {
           <div className="bg-white rounded-lg shadow-xl w-full max-w-lg mx-4">
             {/* Modal Header */}
             <div className="flex items-center justify-between px-6 py-4 border-b border-gray-200">
-              <h2 className="text-xl font-semibold text-gray-800">New Requirement</h2>
+              <h2 className="text-xl font-semibold text-gray-800">{t('createModal.title')}</h2>
               <button
                 onClick={closeCreateModal}
                 className="text-gray-400 hover:text-gray-600"
@@ -1029,7 +1033,7 @@ export default function RequirementsPage() {
                 {/* Tag Selection */}
                 <div>
                   <label className="block text-sm font-medium text-gray-700 mb-1">
-                    Tag <span className="text-red-500">*</span>
+                    {t('createModal.tag')} <span className="text-red-500">*</span>
                   </label>
                   <select
                     value={newReqTagId}
@@ -1037,7 +1041,7 @@ export default function RequirementsPage() {
                     className="w-full px-3 py-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 focus:border-transparent"
                     required
                   >
-                    <option value="">Select a tag...</option>
+                    <option value="">{t('createModal.selectTag')}</option>
                     {tags.map((tag) => (
                       <option key={tag.id} value={tag.id}>
                         {tag.tag_code} - {tag.tag_description}
@@ -1049,13 +1053,13 @@ export default function RequirementsPage() {
                 {/* Requirement Name */}
                 <div>
                   <label className="block text-sm font-medium text-gray-700 mb-1">
-                    Name <span className="text-red-500">*</span>
+                    {t('createModal.name')} <span className="text-red-500">*</span>
                   </label>
                   <input
                     type="text"
                     value={newReqName}
                     onChange={(e) => setNewReqName(e.target.value)}
-                    placeholder="Enter requirement name"
+                    placeholder={t('createModal.namePlaceholder')}
                     className="w-full px-3 py-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 focus:border-transparent"
                     required
                   />
@@ -1064,12 +1068,12 @@ export default function RequirementsPage() {
                 {/* Description */}
                 <div>
                   <label className="block text-sm font-medium text-gray-700 mb-1">
-                    Description
+                    {t('createModal.description')}
                   </label>
                   <textarea
                     value={newReqDesc}
                     onChange={(e) => setNewReqDesc(e.target.value)}
-                    placeholder="Enter requirement description (optional)"
+                    placeholder={t('createModal.descriptionPlaceholder')}
                     rows={3}
                     className="w-full px-3 py-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 focus:border-transparent resize-none"
                   />
@@ -1078,14 +1082,14 @@ export default function RequirementsPage() {
                 {/* Priority Selection */}
                 <div>
                   <label className="block text-sm font-medium text-gray-700 mb-1">
-                    Priority
+                    {t('createModal.priority')}
                   </label>
                   <select
                     value={newReqPriorityId}
                     onChange={(e) => setNewReqPriorityId(e.target.value ? Number(e.target.value) : '')}
                     className="w-full px-3 py-2 border border-gray-300 rounded text-sm focus:outline-none focus:ring-2 focus:ring-teal-500 focus:border-transparent"
                   >
-                    <option value="">Select a priority (optional)...</option>
+                    <option value="">{t('createModal.selectPriority')}</option>
                     {priorities.map((priority) => (
                       <option key={priority.id} value={priority.id}>
                         {priority.priority_name} ({priority.priority_num})
@@ -1097,7 +1101,7 @@ export default function RequirementsPage() {
                 {/* Groups Selection */}
                 <div>
                   <label className="block text-sm font-medium text-gray-700 mb-2">
-                    Groups
+                    {t('createModal.groups')}
                   </label>
                   <div className="grid grid-cols-2 gap-2 max-h-40 overflow-y-auto border border-gray-200 rounded p-3">
                     {groups.map((group) => (
@@ -1123,14 +1127,14 @@ export default function RequirementsPage() {
                   className="px-4 py-2 border border-gray-400 rounded text-sm font-medium text-gray-700 hover:bg-gray-100"
                   disabled={createLoading}
                 >
-                  Cancel
+                  {tCommon('cancel')}
                 </button>
                 <button
                   type="submit"
                   className="px-4 py-2 bg-teal-600 text-white rounded text-sm font-medium hover:bg-teal-700 disabled:opacity-50 disabled:cursor-not-allowed"
                   disabled={createLoading}
                 >
-                  {createLoading ? 'Creating...' : 'Create Requirement'}
+                  {createLoading ? t('createModal.creating') : t('createModal.createButton')}
                 </button>
               </div>
             </form>