var gathering = {     
	addEvent: function(elm, evType, fn, useCapture) {
		if (! elm) return;
		if (elm.addEventListener) {
			elm.addEventListener(evType, fn, useCapture);
			return true;
		} else if (elm.attachEvent) {
			var r = elm.attachEvent('on' + evType, fn);
			return r;
		} else {
			elm['on' + evType] = fn;
		}
	}
}

var gatheringEvents = {		
	init: function() {	
		gathering.addEvent(document.getElementById('layerTriggerOne'), 'click', function (e) { gatheringEvents.showLayer('layerOne'); gatheringEvents.preventDefault(e);}, false);
		gathering.addEvent(document.getElementById('layerTriggerTwo'), 'click', function (e) { gatheringEvents.showLayer('layerTwo'); gatheringEvents.preventDefault(e);}, false);
		gathering.addEvent(document.getElementById('layerTriggerThree'), 'click', function (e) { gatheringEvents.showLayer('layerThree'); gatheringEvents.preventDefault(e);}, false);		
		gathering.addEvent(document.getElementById('closeOne'), 'click', function (e) { gatheringEvents.hideLayers(); gatheringEvents.preventDefault(e);}, false);
		gathering.addEvent(document.getElementById('closeTwo'), 'click', function (e) { gatheringEvents.hideLayers(); gatheringEvents.preventDefault(e);}, false);
		gathering.addEvent(document.getElementById('closeThree'), 'click', function (e) { gatheringEvents.hideLayers(); gatheringEvents.preventDefault(e);}, false);
	},
	
	preventDefault: function(e) {
		e.preventDefault? e.preventDefault() : e.returnValue = false; 
	},
	
	showLayer: function(e) {
		document.getElementById('layerOne').style.display = "none";	
		document.getElementById('layerTwo').style.display = "none";	
		document.getElementById('layerThree').style.display = "none";	
		document.getElementById(e).style.display = "block";	
	},
	
	hideLayers: function(e) {
		document.getElementById('layerOne').style.display = "none";	
		document.getElementById('layerTwo').style.display = "none";	
		document.getElementById('layerThree').style.display = "none";				
	}
}

if (document.getElementById) {
	gathering.addEvent(window, "load", gatheringEvents.init, false);
}