Date: 02/15/07 (WebDesign)    Keywords: css, html, web

I need help seeing what's screwing up in a little thrown together navigation:
http://www.scottopic.com/testnav/News_Releases2.html
It's all onClick events which are supposed to open and close similar to a file tree, and then close out all of other top level options whenever another top level choice is clicked.
It uses simple a simple Show/Hide script to toggle the display state of the secondary navigation layers from display: none to display: block and back.

Simple,right?

Well, I was happily pretending like I knew what I was doing in IE6, and while it's code-ugly, it did the job.
But now looking at it in IE7, the display of the sub-navigation layers seem to essentially open behind the main navigation. If you click "Dentists:, it essentially works right, but then see the problem as you click "Agents/Brokers", "Purchasers" and so on - above a certain point, it looks like nothing is happening.

Any hints or ideas what may be going wrong here?
I'm not necessary asking for anyone to reshape the code, but a poke for my cobwebby brain may help out here, including outright faults in my code/styles and/or esoteric problems in IE7.

Handy link to the CSS:
http://www.scottopic.com/testnav/nav1.css

Note: it also does a similar 'trick' in Firefox, but that's not the primary concern at this stage.

Source: http://community.livejournal.com/webdesign/1222223.html