- Introduced CSS custom properties for spacing, typography, colors, and shadows.
- Developed styles for form sections, grids, invoice items, and summary components.
- Implemented responsive design adjustments for various screen sizes.
- Added utility classes for text, spacing, and flex layouts.
- Included dark mode and high contrast mode support.
- Established loading states and validation/error styles.
- Enhanced accessibility features with focus styles and screen reader utilities.
