Div anchors scrolling too far
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I'm using a static bar at the top of my site, about 20px high. When I click an anchor link(for those who don't know, the navigation on wikipedia works like that. Click a title and the browser goes down to it) part of the text disappears behind that top bar.

Is there any way to stop this from happening? I'm not in a position where I can use an iFrame. Onlything I can think of is make it scroll back a bit each time, but is there another way? Some CSS setting to manipulate the body or something?