Shoutbox

Is it possible to stretch an image (or resize it) to the boundries of the element that it is located in? Basically, I am having a problem with my toasts:


The background I am using is about 1600x1200, which is obviously way bigger than the toasts, and it seems that it's only showing a portion of the image. I am using the same image for my main background of WLM, and it stretches and resizes with WLM, but I can't figure out how it does it.

So is there a way to make a large image scale down to fit within the boundries of the element that it is located in?

Thanks .