The solution, unfortunately, is not as simple as that.
Style sheets are still restricted to two alternating colours. What I'm attempting to do is manually dictate what colour the cell background carries of a particular column. So in other words, the column under forums would be white, the columns displaying the number of posts would have a blue background, and so on. This, I cannot do at all using style sheets.
The only remaining option therefore, is to tweak the code within the Perl scripts themselves. Once I know which lines to modify, I'll be in a much better position towards accomplishing that goal.