Hello. =)

I'm trying to create some fake "tabs":
Example #2 (how it looks on my actual layout)
The external CSS file

This layout looks fine in Internet Explorer. But in Firefox, when you hover on the tabs, the top border disappears. And NONE of the tabs are directly on top of the "table".

Please help. =(

You need to take care of validation errors on your CSS first and move on from there.