function showhide(layer_ref) 
{
	//alert('tu');
	
	document.getElementById('sub1').style.display = 'none';
	document.getElementById('sub2').style.display = 'none';
	document.getElementById('sub3').style.display = 'none';
	document.getElementById('sub4').style.display = 'none';
	document.getElementById('sub5').style.display = 'none';

	
	document.getElementById('a1').className = 'anch_big';
	document.getElementById('a2').className = 'anch_big';
	document.getElementById('a3').className = 'anch_big';
	document.getElementById('a4').className = 'anch_big';
	document.getElementById('a5').className = 'anch_big';

	
	hza = document.getElementById('sub'+layer_ref);
        hza.style.display = 'block';
	hzb = document.getElementById('a'+layer_ref);
	hzb.className = 'for_js';
	
}