// selectively show/hide divs
var state = 'none';

function showhide(layer_ref) {
	if (state == 'block') {
		state = 'none';
	}
	else {
		state = 'block';
	}
	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;
	}
}