Enhance Navbar UI and User Experience

[manaswiniiyer]

Changes Made

• Added orange-tinted gradient background to navbar
• Improved nav link styling with orange color and hover effects
• Added active link indicator with orange dot
• Enhanced search bar with orange border and focus expand effect
• Improved Sign In button with orange outline and fill on hover
• Added sticky navbar with subtle shadow

Files Changed

• static/css/style.css

[manaswiniiyer]

Hi @KDeekshita , I've submitted PR of Navbar Enhancement
Please review when you get a chance. Thank you!