Dark mode

[naftis]

Maybe create a simple theming ability for the frontend and create some kind of dark theme?

[eioo]

Maybe we should ditch the current theme.scss file and start using something like useTheme custom react hook to handle the theming?

There's also this but not too sure what it does and it has not been updated recently: https://github.com/donavon/use-dark-mode