// JavaScript Document

var timeout	= 500;
var closetimer	= 0;
var menuitem	= 0;

// open hidden layer
function menuopen(id)
{	
	// cancel timer
	menucanceltime();

	// close old layer
	if(menuitem) menuitem.style.visibility = 'hidden';

	// get new layer and show it
	menuitem = document.getElementById(id);
	menuitem.style.visibility = 'visible';

}
// close displayed drop down menu
function menuclose()
{
	if(menuitem) menuitem.style.visibility = 'hidden';
}

// close timer
function menuclosetime()
{
	closetimer = window.setTimeout(menuclose, timeout);
}

// cancel timer
function menucanceltime()
{
	if(closetimer)
	{
		window.clearTimeout(closetimer);
		closetimer = null;
	}
}