This is a very easy way I get a background color on my ebay listings.
When I'am listing my painting and I come to the description section I fill in the description then at the top of that area it says standard then next to it it says html click that, then on the end of the very last line type this
<Body bgcolor="000000"> then I proceed with my listing
This is the html for a black background
Oh yeh I make sure I change the font color first
Here is a link for html color codes www.html-color-codes.com
I hope this will help anyone who is interested