Button Question - recognise hit state

Hi there,

Just got back into Flash after a 3 year break, things have certainly changed!

Anyway i’m building a gallery section of a site which will have about 20 small buttons which will display various client images.

I want the buttons, when pressed, to change appearance so that the user knows where he/she has been.

You can see this in action on http://www.dixonfilm.com/ in the film or photography section.

I’m sure it’s very simple but as i said it’s been a long time. Any help will be much appreciated

Cheers

Dan