Transparency, Opacity, or Alpha settings for CSS Backgrounds

Try:

background:rgba(r,g,b,alpha-value)

Voila!
For example, on this blog, I use rgba(255,255,255,0.8) for the background wrapper.

Cite as:
Saad, T. "Transparency, Opacity, or Alpha settings for CSS Backgrounds". Weblog entry from Please Make A Note. http://pleasemakeanote.blogspot.com/2010/07/transparency-opacity-or-alpha-settings.html