Need help with CSS (position: fixed)

I’ve got a problem with my site concerning the styling. I’ve set the position of the navbar to “fixed” and everything shows up just fine in firefox, but since IE doesn’t support “position: fixed” i want to style the navbar seperately only for IE (want to keep “fixed” in FF, but fix the layout for IE, so that it doesn’t look crappy). Any suggestrions?

> https://lipa.skip.pl