<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>CSS Test: Test for containing block for absolutely positioned elements being initial containing block</title> <link rel="author" title="Robert O'Callahan" href="mailto:robert@ocallahan.org" /> <link rel="author" title="Mozilla Corporation" href="http://mozilla.com/" /> </head><body style="margin:0"> <div style="position:fixed; width:50%; height:50%; left:50px; top:50px; border:10px solid black;"></div> </body></html>