CSS broken, after restoring original css directory from github

Hello, good people!

After playing around with custom.css, I had a problem I could not fix. As I wasn’t sure whether I might have tried tweaking the original files too, I decided to download the media/css directory from github in order to replace mine with the original files. After that, my webinterface looks like this:

Should I not have done that? I don’t get how that could have messed up the webinterface.

I also noticed, that now my browser loads a css from the CACHE directory, instead of seahub.css. Deleting media/CACHE and /tmp/seafile_cache was suggested in order to fix this, yet everytime I restart seahub, seafile and firefox, those two directories are being recreated.

Any ideas anyone?