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;