[FEATURE REQUEST] Upgrade Tailwind CSS from v3 to v4

[treoden]

Is your feature request related to a problem? Please describe. Tailwind CSS v4 has been released with new features, improved performance, and better future-proofing. The project currently uses Tailwind CSS v3, which may limit access to newer capabilities and improvements.

Describe the solution you'd like Upgrade Tailwind CSS from version 3 to version 4 throughout the codebase.

Additional context Review all breaking changes and update configurations, dependencies, and component classes as necessary to ensure compatibility with Tailwind v4.