Should work in most modern browsers, but hasn't been tested. This is still under heavy development! Changing the colors isn't suggested as it isn't very robustly made. I mostly just have them for macros in my own css, but feel free to try and tweak them! Best results will probably be with a default styled trello board in chrome using the default style settings. Hopefully I can make that a bit more flexible in the future.

Check out the git repo here: https://github.com/fresham/userstyles