- Replace inline CSS with Tailwind classes
- Improve page layout and scaling
- Add icons to ControlBar
- Small refactor of play/pause logic
- Add basic (not by any means final) colours
It is unclear whether these are actually significantly improving
performance and they add non-trivial complexity to the codebase,
especially when under heavy frontend development. Removing most of them
for now until it can be shown they are actually worthwhile.