Special:Badtitle/NS90:User talk:Vorticity/Highlight working Wikipedia tabs?

Hey, Brent. Could you do a thing for me, please?

In the subpage menu, I'd like to make it so that, in any given instance of the subpage header templates, the Wikipedia tab changes its appearance if the wppage parameter in the template has been defined (i.e. wppage=Some_Article's_Title_Here). Perhaps the tab and/or text could change color.

It seems that I can't program this sort of thing directly into the template definition, even if it's just a change to the text. The .css file needs to be edited in order to implement such a function. But I can't make heads or tails out of the .css file, so I'm relying on you to make this change.