function layer_show(layer_name, action) {
	if (action == "show") {
		document.getElementById(layer_name).style.visibility = "visible";
		if(layer_name == "buy")
			document.getElementById("download").style.visibility = "hidden";
		if(layer_name == "download")
			document.getElementById("buy").style.visibility = "hidden";
	} else  if (action == "hide") {
		document.getElementById(layer_name).style.visibility = "hidden";
	}
}