Creating styles for different a tags

so im updating this wordpress blog for someone else, and I noticed that there is a style for all <a> tags giving the links a background-color: of blue.

ok that’s fine. For the links that I don’t want a blue rollover bg, I just give it its own id so

div#link a:hover{background-color:#FFFFFF}

but it still gives it a bg that matches the website background. It works in firefox, but IE when you rollover the white bg pushes everything below the link slightly.

Is there a way to say apply no background?