function showhide(layer_ref){
	
	if (document.all) { //IS IE 4 or 5 (or 6 beta)
		state=document.getElementById(layer_ref).style.display;
		//eval( "state=document.all." + layer_ref + ".style.display");
	}
	if (document.layers) { //IS NETSCAPE 4 or below
		state = document.layers[layer_ref].display =  'none';
	}
	if (document.getElementById &&!document.all) {
		hza = document.getElementById(layer_ref);
		state = hza.style.display;
	}
	
	if(state == "none"){
		show(layer_ref);
		}else{
		hide(layer_ref);
	}
	hza = document.getElementById(layer_ref);
	if(hza.className == 'cache'){
		show(layer_ref);
	}else{
		hide(layer_ref);	
	}
}

function hide(layer_ref) {
	hza = document.getElementById(layer_ref);
	hza.className='cache';
	
	//ancienne version de IE ?
	if (document.all) { //IS IE 4 or 5 (or 6 beta)
		eval( "document.all." + layer_ref + ".style.display = none");
		eval( "document.all." + layer_ref + ".style.visibility = hidden");
		eval( "document.all." + layer_ref + ".style.position = absolute");
	}
	if (document.layers) { //IS NETSCAPE 4 or below
		document.layers[layer_ref].display =  'none';
		document.layers[layer_ref].position =  'absolute';
	}
	if (document.getElementById) {
		hza = document.getElementById(layer_ref);
		hza.style.display =  'none';
		hza.style.position =  'absolute';
	}
	
}

function show(layer_ref) {
	hza = document.getElementById(layer_ref);
	hza.className='apparent';
	
	//ancienne version de IE ?
	if (document.all) { //IS IE 4 or 5 (or 6 beta)
		eval( "document.all." + layer_ref + ".style.display = block");
		eval( "document.all." + layer_ref + ".style.position = relative");
	}
	if (document.layers) { //IS NETSCAPE 4 or below
		document.layers[layer_ref].display =  'block';
		document.layers[layer_ref].position =  'relative';
	}
	if (document.getElementById) {
		hza = document.getElementById(layer_ref);
		hza.style.display =  'block';
		hza.style.position =  'relative';
	}
	
}