var state = 'block';
function showhide(layer_ref){
	
	if(document.all){ //IS IE 4 or 5 (or 6 beta)
		eval("document.all." +layer_ref+ ".style.display = state");
	}
	if (document.layers) { //IS NETSCAPE 4 or below
		document.layers[layer_ref].display = state;
	}
	if (document.getElementById &&!document.all) {
		hza = document.getElementById(layer_ref);
		hza.style.display = state;
	}

}