Dark Mode for WebUI

[EvilSquirrelGuy]

Is your feature request related to a problem? Please describe. The web UI uses a bright colour scheme, this is sometimes problematic when using it later in the day (or at all)

Describe the solution you'd like For the colour scheme in the WebUI to be changed to a dark one, or for a toggle to be added

Describe alternatives you've considered Modifying the css using Developer Tools

Additional context After modifying with dev tools