Proposal: Red variation of default themes

Hi, I think lemmygrad.ml should use variations of the default light/dark themes with red accents instead of green.

• Keeping the layout similar yet colors distinct from other instances (especially lemmy.ml) makes it clear that you are on the same kind of site but a different instance, and that this one is very much red
• This is an easy fix to make (changing a few color codes in the .css files)