Here's the relevant piece of code.
<div style="position:relative;height:506;width:700; z-index:1;
<div style="position:absolute;z-index:2; height:0; width:0;">
<img src="images/Frame-Brown-Land.png" alt="" />
<div style="position:absolute;top:100px; left:125px;">
<img src="images/poster1.jpg" alt="" />
In strict mode, anything that follows this appears below the output
(and the background image isn't displayed). In quirks mode, which I'd
prefer to avoid, the output is as I expected (the basic idea is to
simulate the appearance of a framed/matted poster). Any ideas what I'm
doing wrong with my css?