Quick hack for http://gameaboutsquares.com/; if that game gets a new theme or change structure, this style will most probably break.

Not sure about colours names; change `content`s to your liking (maybe just 'A','B','C','D' would be most appropriate for playing?).

It is also possible change actual colours with CSS3 patterns (or images). I have tried but haven't achieved anything pleasant.

Changelog:
2014-08-03 Fixed level 21: disabled patterns and re-introduces labels. Disabled rotation at level 29.

https://news.ycombinator.com/item?id=8092566