Hi, I've published all the custom CSS that I use on my PieFed instance. It's inspired by the Mint color palette from Voyager. It's almost a theme, but for now I'll keep it all in custom CSS to keep things simple.
It's only optimized for darkmode, for now.
If you don't like mint, you can change the main color variable --bs-base-color in line 7 and 17 to a color of your liking. That'll change the base color for everything, except the logo, that's a png from my codeberg repo (corresponding logo code starting at line 108). I tried filtering the original blue PieFed logo to mint with something like filter: hue-rotate(305deg) but it wasn't quite right.
You can find the code on codeberg.
And you can see a demo running on my instance.
Have a nice day :)