Yeah, editing the css is easier -- thanks.
Try this: try setting up different colors for different numbers of "thanks." As far as I can tell, no matter how many colors you define, the first level is the only one that works - all posts, no matter how many thanks above the first number are the same color.
---------- Post added 30th October 2011 at 08:04 ---------- Previous post was 29th October 2011 at 21:38 ----------
A quick follow up - I made 4 clicks yellow and then, just trying to make it work, 6 clicks result in red. It didn't make any difference for me (using Chrome but I don't know if that has anything to do with it). Since it didn't make any difference to me, I forgot to change it back. This morning I had some users complaining about the red background...so it did work.