function showBubble(event) {
  var posx = 0;
	var posy = 0;
	if (!event) var e = window.event;
	if (event.pageX || event.pageY) 	{
		posx = event.pageX;
		posy = event.pageY;
	}
	else if (event.clientX || event.clientY) 	{
		posx = event.clientX + document.body.scrollLeft
			+ document.documentElement.scrollLeft;
		posy = event.clientY + document.body.scrollTop
			+ document.documentElement.scrollTop;
	}
  var bubble = document.getElementById('bubble');
  bubble.parentNode.style.cursor = "help";
  bubble.style.display = "block";
  bubble.style.position = "absolute";
  bubble.style.top = posy-200+"px";
  bubble.style.left = posx-90+"px";
}
function hideBubble() {
  var bubble = document.getElementById('bubble');
  bubble.style.display = "none";
  bubble.parentNode.style.cursor = 'auto';
}
function hideText() {
  var bubble = document.getElementById('bubble');
  bubble.innerHTML = '';
}