I don't see any background color specified in the markup, and I'm not even sure it was possible to do that at that time.
The first web page I saw, in one of Netscape's first version, was later, but I remember that Netscape found it cool to have a grayish background back then rather than a white one. I think Mosaic had a gray background too. What was the browser used to display that first web page? How did it look like?