I think that the simplest solution to the problem is to look at the source code of the page in question then try it on your own site.
Here, (http://www.thinkdigitally.com/) the code in question was:
<BODY BGCOLOR=#666666 LEFTMARGIN=0 TOPMARGIN=0 MARGINWIDTH=0 MARGINHEIGHT=0>
But remember, not all browsers will display the code in the same way. There are folks out there using some VERY OLD browsers and it ain't because they're stupid.