Deleting / Reappearing Tabs

I got a code for the CSS style sheet to hide my faq tab a while ago and it worked fine until now. It re appeared and the code wouldn't work. I just deleted the FAQ image and now there is a gap between my tabs. How can I fix this? I'm assuming fixing it so it doesn't display would fix the gap and also fix another small gap I have.

Here is what I need ;

-Solution to code or a different code to hide the FAQ tab all together
-Code to hide the usergroups tab all together

The code I am using ;

a.mainmenu[href="/faq.htm"] {
display:none;
}

Thanks alot in advance.

Because the url's have been updated. Its no longer /faq.htm is /faq