Forum Underline Links
 

How do I remove the underline from forum category titles?

I wanted my forum and sub-forum names to be underlined links, and also when someone post a link, I want it to be underlined, so I enabled it under link_textdecoration. But that enables it for every link on the site!!

I also want to remove the underline from the New Thread, New Post buttons too. How to control the underline for these links separately?