Board Thread:Support Requests - Designing Your Wikia/@comment-3135378-20151205215003/@comment-4731443-20151205231244

The first rule below applies to both the primary tabs and its subtabs. The second rule only applies to the primary tabs. You may find that preferable since I can't think of a way to change the navigation bar's underlying color based on the active tab (without JavaScript anyway). .nav-item:nth-child(1), .nav-item:nth-child(1) .subnav-2a { background-color: saddlebrown !important; } .nav-item:nth-child(2) { background-color: green !important; }

All you need to change is the number between parentheses for each corresponding tab and its assigned color as it suits you :)

I'll leave it up to you to determine whether this change is against the Terms of Use, but I don't think only changing colors would be a big deal.
 * Not to intentionally block, remove, or otherwise obstruct the proper functioning and view of advertisements, and/or user interface and functionality by other users, including but not limited to changing or adding javascript or CSS changes to the Service that would prevent the proper display or function of advertisements and/or user interface and functionality; [emphasis mine]