Z-index: How to make nested elements appear underneath their parent element

[yap_jp]

This fiddle should demonstrate the issue:http://jsfiddle.net/5sqxQ/2/I want the sub menu to appear underneath the parent menu. I was then was looking to extend this with JavaScript to slide the menu from underneath on hover of the parent li element.Not fussed about the JavaScript but can't figure out how to style the elements to achieve the desired layering.