Can you share a link to your site please?
The #rt-top-surround div actually contains the background that spans the entire page. You'll have to remove it and reassign the same color/image to the #rt-top-surround .rt-container div. It would look something like this:#rt-top-surround {background: none;}
#rt-top-surround .rt-container {-webkit-gradient(linear,0 0,0 100%,from(#3B3B3B),to(#2E2E2E))}