var delay = 100;
var closetimer = 0;
var ddmenuitem = 0;

// open hidden layer
function mopen(id)
{
	// cancel close timer
	mcancelclosetime();
	// close old layer`s
	mclose();

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

	// get new layer and show it
	if(id == 'm1')
	{
		document.getElementById('a1').style.color = '#333';
		document.getElementById('a1').style.backgroundColor = '#f0f0f0';
	}
	if(id == 'm2')
	{
		document.getElementById('a2').style.color = '#333';
		document.getElementById('a2').style.backgroundColor = '#f0f0f0';
	}
	if(id == 'm3')
	{
		document.getElementById('a3').style.color = '#333';
		document.getElementById('a3').style.backgroundColor = '#f0f0f0';
	}
	if(id == 'm4')
	{
		document.getElementById('a4').style.color = '#333';
		document.getElementById('a4').style.backgroundColor = '#f0f0f0';
	}
}

// close showed layer
function mclose()
{
	document.getElementById('m1').style.visibility='hidden';
	document.getElementById('m2').style.visibility='hidden';
	document.getElementById('m3').style.visibility='hidden';
	document.getElementById('m4').style.visibility='hidden';

	document.getElementById('a1').style.color = '#fff';
	document.getElementById('a1').style.backgroundColor = '#333';

	document.getElementById('a2').style.color = '#fff';
	document.getElementById('a2').style.backgroundColor = '#333';

	document.getElementById('a3').style.color = '#fff';
	document.getElementById('a3').style.backgroundColor = '#333';

	document.getElementById('a4').style.color = '#fff';
	document.getElementById('a4').style.backgroundColor = '#333';
}

// go close timer
function mclosetime()
{
	closetimer = window.setTimeout(mclose, delay);
}

// cancel close timer
function mcancelclosetime()
{
	if(closetimer)
	{
		window.clearTimeout(closetimer);
		closetimer = null;
	}
}
// close layer when click-out
document.onclick=mclose;