Remove unused CSS
Remove unused CSS

This CSS has not been in use since
https://github.com/houndci/hound/commit/8c24be214aae1642dbe4e7fb9e850bf8a20527de

houndci/hound,houndci/hound,thoughtbot/hound,houndci/hound,thoughtbot/hound,thoughtbot/hound,houndci/hound,thoughtbot/hound