I'm using some simple javascript to hide and then show a box using document.getElementById('box').style.display. In Firefox it works perfectly, but in IE the box appears in the main content area until you hover over it.

Click on the "Get rid of this box" link on the left and then on the "I want the box back!" link and you'll see what I mean. I reckon this is something to do with the fact the box is floated left with a negative margin. How can I solve this?