On my testpage http://shop.mommersontwerp.nl I have a really strange thing happening. There is a borderline right below the header in Firefox. It's not supposed to be there.
When I enlarge the view it's gone. When decreasing the view it takes 2 steps and then it's gone again.
It's not visible in Chrome or in Safari, so the logical conclusion is, that it's a Firefox-thing and not a Pagelines-thing. I just have no idea how to fix this. Anybody familiar with this problem?