Div not auto-sizing in Firefox

Anyone care to check this page out in any web dev tool (Firebug, IE9, Chrome Dev Tools) and tell me why the #container div would not be auto-sizing in Firefox? There is su开发者_如何学JAVApposed to be a background shadow, which is visible in most browsers, but not showing up in FF. Thoughts?

http://d2burke.com/hosted/vaacme/

Thanks!

Since all elements inside #container are floated, everything inside it is taken out of the normal document flow, and thus it shrinks to nothingness, since it has zero padding and height. To fix this you can either apply:

#container {
    overflow: hidden;
}

or remove:

.break {
    float: left;
}