Well, I think changing it is the easy bit: a _quick_ look suggests that in the file apidb.css one only has to change the styles
48 .platinum {background-color: #ECECEC; }
49 .gold { background-color: #FFF600 }
50 .silver { background-color: silver; }
51 .bronze { background-color: #FCBA0A; }
52 .garbage { background-color: #999966; }
to the agreed colours. As suggested by hakum, the main issue is to agree on a new set of colours. I'm not inclined to suggest a scheme myself because I'm a programmer not a designer, but a search on the net will find something...
