UBB.threads PHP Forum Software Community Forums UBB.threads 6 Version 6 Support Where are these in the Style sheet?

One item I am having trouble finding in the Style sheets:
1. Which item controls the color of the minus sign and question mark that are in the little boxes in the Category bar? (the icons you use to collape a category and the ? you use to see the description of the category? Are these controled in the style sheets or are they images?
Basil

There is a style class called .newpostsincat that control the new color of the +/- sign. But we currently don't have a class in place to control the background color of the +/- sign when there are no new posts or the question mark.

Thanks!