var timeout = 500;
var closetimer = 0;
var ddmenuitem = 0;

function nav_menu_open() {
	nav_menu_canceltimer();
	nav_menu_close();
	ddmenuitem = $(this).find('ul').css('visibility', 'visible');
}

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

function nav_menu_timer() {
	closetimer = window.setTimeout(nav_menu_close, timeout);
}

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

$(document).ready(function() {
	$('.nav-menu-top > li').bind('mouseover', nav_menu_open);
	$('.nav-menu-top > li').bind('mouseout',  nav_menu_timer);
});

document.onclick = nav_menu_close;