you have to re-color the image ...menu.gif I think. check the css for "menu" and it will tell you what image to modify...if it's not in the css, then check the header page where the menu is.

Also, be aware that changing just the code in css is NOT enough to change the entire site. There are many many many references to the colors in each and every .tpl file, as well as depreciated code like the <font> tag (I'm currently working to get rid of those).