var timeout = 500;
var hide_time = 0;
var menu_I = 0;

function mopen(id)
{	
	mcancelclosetime();
	if(menu_I) menu_I.style.visibility = 'hidden';
	menu_I = document.getElementById(id);
	menu_I.style.visibility = 'visible';
}

function mclose()
{
	if(menu_I) menu_I.style.visibility = 'hidden';
}

function mclosetime()
{
	hide_time = window.setTimeout(mclose, timeout);
}
function mcancelclosetime()
{
	if(hide_time)
	{
		window.clearTimeout(hide_time);
		hide_time = null;
	}
}
document.onclick = mclose;