Primary links as tabs in Navbar

I've been pulling my hair out trying to create tab like buttons in the navbar just like you see on this page at the top from Primary links. I have no problem making it work for "#primary a" but that's as far as it goes. Once clicked the buttons disappear unless hovered. I played with every single setting in both CSS files for the color scheme I'm using but nothing seems to make a difference.

What am I missing? The font goes black and the button I made disappears once clicked and remains that way no matter what I do in the css so I can't track it down. Is it even controlled within this theme? I attacked an image just incase I haven't explained myself properly.

Thanks
Jon
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