Remember, dear reader and also future Brendan, an attribute that’s hyphenated in CSS is camelCapped in Javascript! So background-image becomes style.backgroundImage. For no real reason except psychotic, alias-hating adherence to meaningless language conventions.
While I’m at it, ROLLOVER HIGHLIGHT IMAGES ARE GODDAMN POINTLESS. Nobody cares about them except graphic designers who have never written a web page, and even they ignore them on every site but the ones they themselves mocked up.
(Yes, I know rollovers need not make use of Javascript. These two blurts are only sort of related.)
Punch line!