// JavaScript
var currentLayer = "copy1";

function showLayer(argLayer) {
	document.getElementById(currentLayer).style.display = "none";
	document.getElementById(argLayer).style.display = "block";
	
	currentLayer = argLayer;
}

function showNext(argTotal) {
	var nextLayer;
	var t = new String(currentLayer);
	
	t = t.replace("copy","");
	t = new Number(t);
	
	if (t < argTotal) {
		nextLayer = t + 1;
		nextLayer = "copy" + nextLayer;
	} else {
		nextLayer = "copy1";
	}
	document.getElementById(currentLayer).style.display = "none";
	document.getElementById(nextLayer).style.display = "block";
	
	currentLayer = nextLayer;
}

function showPrev(argTotal) {
	var prevLayer;
	var t = new String(currentLayer);
	
	t = t.replace("copy","");
	t = new Number(t);
	
	if (t > 1) {
		prevLayer = t - 1;
		prevLayer = "copy" + prevLayer;
	} else {
		prevLayer = "copy" + argTotal;
	}
	document.getElementById(currentLayer).style.display = "none";
	document.getElementById(prevLayer).style.display = "block";
	
	currentLayer = prevLayer;
}