var timeout	= 100;
var closetimer	= 0;

function showDropdownMenu()
{
	cancelclosetime();
	var elem = document.getElementById("categories-dropdown");
	if(elem)
	{
		elem.style.display = "block";
	}
}

function hideDropdownMenu()
{
	var elem = document.getElementById("categories-dropdown");
	if(elem && closetimer)
	{
		elem.style.display = "none";
	}
}

// go close timer
function closetime()
{
	closetimer = window.setTimeout(hideDropdownMenu, timeout);
}

// cancel close timer
function cancelclosetime()
{
	if(closetimer)
	{
		window.clearTimeout(closetimer);
		closetimer = null;
	}
}