lucy24 - 9:20 pm on Feb 3, 2012 (gmt 0)

Most common reason for valid links not working: Something else on the page is "hiding" the links. That is, humans can see them, but a transparent background (which is the CSS default) prevents the computer from "seeing" them.

If every single bit of your quoted CSS applies to the place where the links are, that's a lot of opportunities for links to get covered up with something else.