// JavaScript Document

function mainmenu(){
$(" #nav ul ").css({display: "none"});
$(" #nav li").hover(function(){
	$(this).find('ul:first:hidden').css({visibility: "visible",display: "none"}).slideDown(300);
	},function(){
		$(this).find('ul:first').slideUp(300);
	});
}
$(document).ready(function(){
	mainmenu();
});
function calcHeight()
	{
	  var the_height=document.getElementById("principal").contentWindow.document.body.scrollHeight;
	  document.getElementById("principal").height=the_height;
	}