Make the site responsive

The site needs to be made responsive to work properly on mobile devices, tablets, and other screen sizes.

## Current Issue
The current layout is not optimized for different viewport sizes, which impacts user experience on smaller screens.

## Expected Behavior
- Responsive design that adapts to mobile, tablet, and desktop screens
- Proper scaling and layout adjustments for different breakpoints
- Touch-friendly interface elements for mobile devices
- Readable text and properly sized buttons across all devices

## Acceptance Criteria
- [ ] Site is fully functional and properly styled on mobile devices (320px - 768px)
- [ ] Site is properly optimized for tablets (768px - 1024px)
- [ ] Desktop experience remains intact (1024px and above)
- [ ] All content is accessible and readable at all breakpoints
- [ ] Navigation is mobile-friendly