var timeout = 500;
var closetimer = 0;
var ddmenuitem = 0;
function nav_open() {
	nav_cancel();
	nav_close();
	ddmenuitem = $(this).find("ul").css('visibility', 'visible');
}

function nav_close() {
	if(ddmenuitem)
		ddmenuitem.css('visibility', 'hidden');
}

function nav_cancel() {
	if(closetimer) {
		window.clearTimeout(closetimer);
		closetimer = null;
	}
}

function nav_timer() {
	closetimer = window.setTimeout(nav_close, timeout);
}

$(document).ready( function() {
	$("#main_nav > li").bind('mouseover', nav_open);
	$("#main_nav > li").bind('mouseout', nav_timer);
	var height = $("#outer_wrap").css('height');
	$("#transparency").css('height', height);
});

document.onclick = nav_close();