Flex - Changing the color of a Custom scrollbar using CSS properties

Currently, I am implementing a scrollbar using a custom embedded image using my CSS stylesheet. This is a very simple, thin scrollbar. I would like to configure this scrollbar using CSS properties 开发者_开发百科at runtime, but so far I have been unable to do so. I know it can be done because I've seen examples of it in the net, but no code to review. Anyone have any suggestions?

Thanks!

This blog has an example that you can view the source of with a right click:

http://www.axelscript.com/2008/02/20/custom-scroll-bar-using-css/

This one has a few links that redirect to examples with image skins:

http://www.foxarc.com/blog/article/101.htm

You can see a lot of the css stuff for scrollbars and pretty much everything else here:

http://examples.adobe.com/flex3/consulting/styleexplorer/Flex3StyleExplorer.html#