Refactor and improve styling system for consistency and maintainability

[mienaiyami]

Issue

The current approach to styles is messy and inconsistent. There are multiple issues affecting maintainability, readability, and user experience.

Rough lists

Few issues

• Too many unused or redundant style variables.
• Inconsistent usage of theme variables across components.
• Some components use hardcoded colors instead of theme values.
• Poor contrast in certain areas, especially in high-contrast or dark modes.
• Misuse of variables leading to incorrect or unintended colors.

Todo

• Audit and remove unused or redundant style variables.
• Standardize theme variable usage across all components.
• Replace hardcoded color values with proper theme tokens.
• Fix high-contrast and accessibility issues.
• Gradually migrate some components to a library like Radix UI (or similar) for better accessibility, styling consistency, and reduced maintenance overhead.

Related issues:

• Side list Divider Color #390
• win contrast theme settings checkbox display issue #359
• dont responsive menu chapter #446