function menuOn(td) {
	var menu = document.getElementById("m" + td.id)
	menu.style.visibility = "visible";
}
		
function menuOff(td) {
	document.getElementById("m" + td.id).style.visibility = "hidden";
}

function hover(event) {
	if(event.target.className == "button") {
		event.target.className = "onButton";
	}
}
		
function noHover(event) {
	if(event.target.className == "onButton") {
		event.target.className = "button";
	}
}