Static DIV inbetween other DIVs

Hello there,

I cannot work out how to achieve the following:

To have a DIV, that acts as a background, which is 100% of the width, and always stays at the visible bottom of the browser.

Behind this DIV, sits the normal background of the page.

Ontop of the DIV (of question), sits another DIV which scrolls containing the page content.

Can anyone fathom my queiry?

I want the DIV to be a transparent gradient you see, and upon scrolling down with the content, the effect would be quite nice…>