/*if(document.getElementById("nav") != null)
{
  var listItems = document.getElementById("nav").getElementsByTagName("li");
  for (i=0; i< listItems.length; i++) {
    listItems[i].onmouseover=function() {
    this.className+=" over";
    }
    listItems[i].onmouseout=function() {
    this.className=this.className.replace(" over", "");
    }
  }
}*/

if(document.getElementById("nav") != null)
{
  var listItems = document.getElementById("nav").getElementsByTagName("li");
  for (i=0; i< listItems.length; i++)
  {
    listItems[i].onmouseover=function()
    {
      this.className+=" over";
      if (this.getElementsByTagName("ul").length == 0)
        this.style.marginBottom = "0";
    }
    listItems[i].onmouseout=function()
    {
      this.className=this.className.replace(" over", "");
    }
  }
}