feat: enhance UI with modern styling and animations

[Lalith0024]

Description

This PR introduces modern UI enhancements to improve the overall look and feel of the personal finance tracker.

Changes Made

• Updated color palette with modern, accessible variables
• Added smooth transitions and hover effects
• Enhanced card components with glassmorphism effect
• Improved base styling for better user experience
• Added responsive design improvements
• Implemented modern button and input styles
• Added new animation classes for smooth transitions

Visual Changes

• Cards now have a subtle glassmorphism effect with smooth hover animations
• Updated color scheme for better contrast and accessibility
• Smoother transitions between states
• Modern form inputs with focus states
• Enhanced typography and spacing

Technical Details

• Updated CSS variables for better maintainability
• Added new utility classes for animations
• Improved performance with hardware-accelerated animations
• Enhanced cross-browser compatibility

Type of change

• New feature (non-breaking change which adds functionality)
• Enhancement (non-breaking change which improves existing functionality)

How Has This Been Tested?

• Verified styling changes across different browsers
• Tested responsive behavior
• Checked animation performance
• Validated color contrast for accessibility