Add responsive navbar styles for various devices

[Dippp10-ally]

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🔧 PR Title

[FEATURE/BUGFIX] Improve Navbar Functionality and Responsiveness

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📄 Summary

This PR improves the navigation bar by enhancing its responsiveness, usability, and overall UI consistency across different screen sizes. It ensures smoother navigation and better user experience on both desktop and mobile devices.

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✨ Changes Made

• Improved responsive design for mobile, tablet, and desktop views
• Fixed alignment and spacing issues in navbar items
• Enhanced hamburger menu behavior on smaller screens
• Added smoother transitions for menu toggle (if applicable)
• Improved accessibility (keyboard navigation / ARIA support if included)
• Refactored CSS/JS for better maintainability

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🧪 Testing Done

• Tested on multiple screen sizes (mobile, tablet, desktop)
• Verified menu toggle functionality
• Checked cross-browser compatibility (Chrome, Firefox, Edge)
• Ensured no layout breaking in existing pages

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📸 Screenshots (if applicable)

Add before/after screenshots or screen recordings here

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🔗 Linked Issue

Fixes #134

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📌 Notes

• No breaking changes introduced
• Navbar is fully backward compatible with existing pages

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[Dippp10-ally]

@JIYAJAIN30 ji , do assign labels called as gssoc:approved , level:intermediate, type:feature , quality:exceptional to above pull request number 136 also.....do merge above pull request number 136 also...