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

// open hidden layer
function mopen(id)

{
	// cancel close timer
	mcancelclosetime();
	
	//close old layer
	if(ddmenuitem)ddmenuitem.style.visibility='hidden';
	
	// get new layer and show it
	ddmenuitem = document.getElementById(id);
	ddmenuitem.style.visibility ='visible';
}	

// close showed layer

function mclose()
{
	if(ddmenuitem)ddmenuitem.style.visibility ='hidden';
}

// go close timer

function mclosetime()
{
	closetimer = window.setTimeout(mclose,timeout);
}

// cancel close timer

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

// close layer when click-out
document.onclick = mclose;