diff --git a/Ralph/IMPLEMENTATION_PLAN.md b/Ralph/IMPLEMENTATION_PLAN.md
index 12d2c54..15657f6 100644
--- a/Ralph/IMPLEMENTATION_PLAN.md
+++ b/Ralph/IMPLEMENTATION_PLAN.md
@@ -159,7 +159,7 @@ src/
 
   Add keyboard navigation throughout. Global shortcuts: Alt+1-7 activate sidebar items, Escape closes expanded items/menus, / focuses search. Sidebar: Up/Down arrows navigate items, Enter activates. Implement focus management: after login, focus moves to first sidebar item; after view change, focus moves to view heading; after expanding item, focus moves to content. Add ARIA: `role="navigation"` on sidebar, `aria-current="page"` on active item, `role="alert"` on clinical alert, proper table markup with `scope="col"`, `aria-expanded` on expandable items. Test with screen reader: views announced, tables navigable, alert read immediately.
 
-- [ ] **Task 14: Implement responsive design (tablet and mobile)**
+- [x] **Task 14: Implement responsive design (tablet and mobile)**
 
   Tablet (768-1024px): Sidebar collapses to 56px icon-only with tooltips on hover. Patient banner always condensed (48px). Tables may horizontally scroll with indicator. Mobile (<768px): Sidebar becomes bottom navigation bar (56px height, 7 icon buttons, safe area padding). Patient banner becomes minimal top bar. Tables switch to card layout (each row becomes stacked card). Search moves to top of each view. Add back navigation arrow in each view. Test all breakpoints: desktop (>1024), tablet (768-1024), mobile (<768). Ensure touch targets minimum 48px. Test on actual mobile device or emulator.
 
diff --git a/Ralph/progress.txt b/Ralph/progress.txt
index 3f96070..ac8c6ac 100644
--- a/Ralph/progress.txt
+++ b/Ralph/progress.txt
@@ -423,3 +423,37 @@ This is a complete redesign of the CV presentation, moving from the ECG animatio
   - useRef array for button refs enables dynamic nav item count
   - Global Escape handler in context prevents need for per-view handlers
   - Focus after login requires ref forwarding from sidebar to context
+
+### Iteration 14 — Task 14: Implement responsive design (tablet and mobile)
+- **Completed**: Task 14 - Implemented full responsive design for tablet and mobile breakpoints
+- **Files created**:
+  - `src/hooks/useBreakpoint.ts` - Custom hook for responsive breakpoint detection (mobile <768px, tablet 768-1024px, desktop >1024px)
+  - `src/components/MobileBottomNav.tsx` - Bottom navigation bar component for mobile with 7 icon buttons and safe area padding
+- **Files modified**:
+  - `src/components/ClinicalSidebar.tsx` - Added tablet mode (56px icon-only sidebar with tooltips) via isTablet prop
+  - `src/components/PatientBanner.tsx` - Added mobile minimal banner and tablet always-condensed mode via isMobile/isTablet props
+  - `src/components/PMRInterface.tsx` - Integrated responsive layout with mobile bottom nav, search bar, and back navigation
+  - `src/components/views/MedicationsView.tsx` - Added mobile card layout with stacked medication cards
+  - `src/components/views/ProblemsView.tsx` - Added mobile card layout for problem entries
+  - `src/components/views/InvestigationsView.tsx` - Added mobile card layout for investigation entries
+  - `src/components/views/DocumentsView.tsx` - Added mobile card layout for document entries
+- **Design decisions**:
+  - Desktop (>1024px): Full 220px sidebar with labels, full/condensed patient banner, standard tables
+  - Tablet (768-1024px): 56px icon-only sidebar with hover tooltips, always-condensed patient banner, tables with horizontal scroll
+  - Mobile (<768px): Bottom navigation bar (56px), minimal patient banner with overflow menu, card layouts instead of tables, search bar at top of each view, back navigation arrow
+  - Mobile card layouts: Each table row becomes a stacked card with expandable content
+  - Touch targets: Minimum 48px height for mobile buttons
+  - Safe area padding: `env(safe-area-inset-bottom)` for bottom nav on devices with home indicator
+- **Responsive patterns**:
+  - `useBreakpoint` hook returns `{ isMobile, isTablet, isDesktop, breakpoint }`
+  - Views conditionally render table or card layout based on `isMobile`
+  - Bottom nav uses fixed positioning with z-index 50
+  - Mobile search bar replaces sidebar search input
+  - Back navigation returns to Summary view from any other view
+- **Quality checks**: `npm run typecheck` ✓, `npm run lint` ✓ (1 pre-existing warning), `npm run build` ✓
+- **Learnings**:
+  - Card layouts work better than horizontal-scrolling tables on mobile
+  - Bottom navigation provides familiar mobile app experience (matches NHS App pattern)
+  - isTablet/isMobile props passed from PMRInterface down to components
+  - useBreakpoint hook avoids resize event listener thrashing with proper cleanup
+  - Mobile overflow menu for banner actions reduces clutter on small screens