I've been using the basic gist of this tutorial to create links with background images that fade to different background images (using a sprite) on hover. This is basically done by putting an empty span inside the link which is hidden until hover, and then it fades in to view.
How can I do the same using a submit button input? I can't just put a span in because obviously you can't insert HTML inside an input tag since it is self-closing. So any other options?
One thing I was thinking was surrounding the input with a div of the same width/height and giving the div the hover background image, and on hover, fade the span out to opacity of something like 0.01 so that it would still be clickable but be transparent. Are there any better options or is this the way to go?