var timeout	= 300;
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(qw)
{
	closetimer = window.setTimeout(mclose, timeout);
}

// cancel close timer
function mcancelclosetime()
{
	if(closetimer)
	{
		window.clearTimeout(closetimer);
		closetimer = null;
	}
}
function a(qw,er)
{
	var url = "url('img/h"+er+"')";
	document.getElementById(qw).style.backgroundImage=url;
}
function b(qw,er)
{
	var url = "url('img/"+er+"')";
	document.getElementById(qw).style.backgroundImage=url;
}
function ab(qw,er)
{
	var url_normal = "url('img/"+er+"')";
	var url_hover = "url('img/h"+er+"')";
	if(document.getElementById(qw).style.backgroundImage==url_hover)
	{
		document.getElementById(qw).style.backgroundImage=url_normal;
	}
	else
	{
		document.getElementById(qw).style.backgroundImage=url_hover;	
	}
}
function ba(qw,er)
{
	var url_normal = "url('img/"+er+"')";
	var url_hover = "url('img/h"+er+"')";
	if(document.getElementById(qw).style.backgroundImage==url_normal)
	{
		document.getElementById(qw).style.backgroundImage=url_hover;
	}
	else
	{
		document.getElementById(qw).style.backgroundImage=url_normal;	
	}	
}
// close layer when click-out
document.onclick = mclose;