First, let me say that I am a long time developer but new to css/php. I am using Rigid Light as the theme for a site I am developing. On my desktop (where I am building the site), the background color in the header/footer is a light tan (#c6c1b0) as specified in the css. On every other machine where I've checked the site, the color is a light to medium gray (looks like about #d6d6d6). Not sure what is happening. Any suggestions for where to look would be helpful.

Thanks