function open_div(id_div) {
				if (document.getElementById(id_div).style.display=='none') {
			document.getElementById('info').style.display="none";
			document.getElementById('guida').style.display="none";
			document.getElementById('map').style.display="none";
			document.getElementById(id_div).style.display="block";
				}
				else {id_div='map';
								document.getElementById('info').style.display="none";
					document.getElementById('guida').style.display="none";
			document.getElementById('map').style.display="block";
					
					}
			if (id_div=='map') { document.getElementById('zoom_mappa').style.display='block';}else{document.getElementById('zoom_mappa').style.display='none';}
			
				
			}