Theming

Comment by @paul-lorenc in the chat:

I did a bit of research into material design, we can refactor our existing color “system” into a proper MaterialTheme which will automatically theme all the material composables. This also allows us to tweak the material composables’ colors, typography, and shape (while sticking to the main material design principles). https://developer.android.com/jetpack/compose/themes

Using MaterialTheme will also allow us to easily implement light/dark mode toggling.