Making a hover effect for a button


This is probably a stupid question, but I am having trouble with it…

I was looking at the Flash MX photogallery with XML tutorial, and ,from what I understand, as long as we have the code correctly, we can have the interface anyway we want.

The problem I am having is how to make the interface. For example, how do you make a simple hover effect for a button? Just changing colors or something?

Can you do it with ActionScript, or is there a better way?

Any help would be greatly appreciated…Thanks in advance.