Javascript menu issue

I have a javascript menu that is loading 70 or so sublinks from 10 main links. It all works fine. I am just having an issue with the menu forcing a big margin at the bottom of page, as if its loaded the menu items while there hidden and expanded the page.

I have attached JS file and CSS file to look at. I can send page to who ever wants to check it out. Its got a lot of code in it, too much to post here.

Hope someone can help