_global.whatLayer="fff";
	
      function showCountDown() {
      	var now = new Date();
      	now = now.getTime();
      	if (endTime - now <=0) {
      	stopTimer();
      	document.getElementById(whatLayer).style.visibility = "hidden";
      	} else {
      		if (running) {
      			timerID = setTimeout("showCountDown()",10);
      		}
      	}
      }
      	
      
      function startTimer() {
      	running = true;
      	now = new Date();
      	now = now.getTime();
      	endTime = now + 500;
      	showCountDown();
      }
      
      function stopTimer() {
      	clearTimeout(timerID);
      	running = false;
      }
      
      function showMenu(whichLayer) {
      	document.getElementById('nan').style.visibility = "hidden";
      	document.getElementById('mv').style.visibility = "hidden";
      	document.getElementById('hhc').style.visibility = "hidden";
      	document.getElementById('fish').style.visibility = "hidden";
      	document.getElementById('ccc').style.visibility = "hidden";
      	startTimer();
      	document.getElementById(whichLayer).style.visibility = "visible";
      	stopTimer();
      }
      
      function hideMenu(whichLayer) {
      whatLayer = whichLayer;
      	startTimer();
      }