window.onload = function() {
	var mainul = document.getElementById('navbar');
	for (var i=0; i<mainul.childNodes.length; i++) {
		mainul.childNodes[i].onmouseover = showSubLevel;
		mainul.childNodes[i].onmouseout = hideSubLevel;
	}
}

function showSubLevel() {	
	var elems = this.getElementsByTagName('ul');
	for (var c=0; c<elems.length; c++) {
		if (c < 1) {
			var ul = elems[c];
			ul.style.display = 'block';
			for (var i=0; i<ul.childNodes.length; i++) {
				ul.childNodes[i].onmouseover = showSubLevel;
				ul.childNodes[i].onmouseout = hideSubLevel;
			}
		}
	}
}

function hideSubLevel() {
	var elems = this.getElementsByTagName('ul');
	for (var c=0; c<elems.length; c++) {
		var ul = elems[c];
		ul.style.display = 'none';
	}
}