feat(landing): improve navbar, typography, and section navigation

[Bivek01]

Summary

This PR enhances the DevTrack landing page by improving navigation, typography, and overall user experience. It introduces a responsive sticky navigation bar with active section highlighting and refines the landing page headings to create a more professional and modern appearance.

Closes #2282

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Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 💥 Breaking change (fix or feature that changes existing behavior)
• 📝 Documentation update
• ♻️ Refactor / code cleanup (no functional change)
• ⚡ UI/UX Improvement
• 🔒 Security fix
• 🧪 Tests only

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What Changed

• Added a responsive sticky navigation bar for improved navigation.
• Implemented active section highlighting while scrolling.
• Added smooth scrolling between landing page sections.
• Improved hero section typography and visual hierarchy.
• Updated section headings for a cleaner and more professional look.
• Enhanced DevTrack branding presentation.
• Improved mobile responsiveness of the navigation menu.
• Added proper section offsets to prevent sticky navbar overlap.

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How to Test

1. Run the application locally using npm run dev.
2. Open the landing page in the browser.
3. Verify navigation links scroll to the correct sections.
4. Scroll through the page and confirm active navigation highlighting updates correctly.
5. Test the layout on desktop and mobile screen sizes.
6. Verify updated typography and section headings are displayed correctly.

Expected result:

• Navigation bar remains sticky while scrolling.
• Active section is highlighted correctly.
• Smooth scrolling works across all sections.
• Updated headings appear professional and readable.
• Layout remains responsive on all screen sizes.

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Screenshots / Recordings

| Before

| After |

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Checklist

• Linked the related issue above
• Self-reviewed my own diff
• No unnecessary console.log, debug code, or commented-out blocks
• npm run lint passes locally
• No TypeScript errors (npm run type-check)
• Added or updated tests where applicable
• Updated documentation / comments if behavior changed

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Accessibility (UI changes only)

• Keyboard navigation works correctly
• Color contrast meets WCAG AA standard
• ARIA labels / roles added where needed
• Tested on mobile / responsive layout

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Additional Context

This PR focuses on improving first-time user experience and navigation clarity while maintaining DevTrack's existing futuristic design language. Before/After screenshots have been attached for easier review.

[github-actions]

GSSoC Label Checklist 🏷️

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