function MostraNascondi(id2){
     if(document.getElementById(id2).style.display){
        document.getElementById('riservata_img').style.top="114px";
        document.getElementById(id2).style.display="";
     } 
     else{
        document.getElementById('riservata_img').style.top="154px";
        document.getElementById(id2).style.display="block";     

     }
}