function showMenu()
{	
	// cancel close timer
	var menu1 = document.getElementById("menu1");
	

	// close old layer
	menu1.style.visibility = 'visible';

}
// close showed layer
function closeMenu()
{
    var menu1 = document.getElementById("menu1");
	menu1.style.visibility = 'hidden';
}

function showMenu2()
{	
	// cancel close timer
	var menu2 = document.getElementById("menu2");
	

	// close old layer
	menu2.style.visibility = 'visible';

}
// close showed layer
function closeMenu2()
{
    var menu2 = document.getElementById("menu2");
	menu2.style.visibility = 'hidden';
}


function showMenu3()
{	
	// cancel close timer
	var menu3 = document.getElementById("menu3");
	

	// close old layer
	menu3.style.visibility = 'visible';

}
// close showed layer
function closeMenu3()
{
    var menu3 = document.getElementById("menu3");
	menu3.style.visibility = 'hidden';
}