I've a problem with an PDF output on my site. Example: http://pdfmyurl.com/?url=www.yomifrog.de/xgm/de/Extended_Game_Mechanics_-_Kapitel_2.php

The background is white. Is there a problem with the PDF export? The original site with a normal browser has still a background-repeat. Or should I use a another css background for the pdf export?