// funzione per prendere un elemento con id univoco
		function prendiElementoDaId(id_elemento) {
			var elemento;
			if(document.getElementById)
				elemento = document.getElementById(id_elemento);
			else
				elemento = document.all[id_elemento];
			return elemento;
		};
		
  function VisualizzaDiv(nome_div) {  
  	  var e = document.getElementById(nome_div);
	    if (e.style.visibility == 'hidden') {
		      e.style.visibility = 'visible';
    		  e.style.display = 'block';
	    } else {
  		    e.style.visibility = 'hidden';
      		e.style.display = 'none';
    	}
  } 
  
function ViewDiv(nomeDiv)
  {  
  var e = document.getElementById(nomeDiv);
  	  alert(e.style.visibility);  
	if ((e.style.visibility == 'hidden') || (e.style.visibility == ''))
	  {
		e.style.visibility = 'visible';
    e.style.display = 'block';
	  }
	else
    {
    e.style.visibility = 'hidden';
    e.style.display = 'none';
    }
  }   
	
  function trim(stringa) {
    while (stringa.substring(0,1) == ' ') {
     stringa = stringa.substring(1, stringa.length);
    }
		while (stringa.substring(stringa.length-1, stringa.length) == ' ') {
      stringa = stringa.substring(0,stringa.length-1);
		}
    return stringa;
	}
	
  function DivMenu(nome_div) {  
	  var e = document.getElementById(nome_div);
		ResetDiv();
    e.style.visibility = 'visible';
	  e.style.display = 'block';			
  }
	
	function ResetDiv() {
			document.getElementById('CatStart').style.visibility = 'hidden';
      document.getElementById('CatStart').style.display = 'none';			
			document.getElementById('HomeCat').style.visibility = 'hidden';
      document.getElementById('HomeCat').style.display = 'none';	
			document.getElementById('CaniCat').style.visibility = 'hidden';
      document.getElementById('CaniCat').style.display = 'none';		
			document.getElementById('SelvaCat').style.visibility = 'hidden';
      document.getElementById('SelvaCat').style.display = 'none';		
			document.getElementById('MezziCat').style.visibility = 'hidden';
      document.getElementById('MezziCat').style.display = 'none';		
			document.getElementById('LiceCat').style.visibility = 'hidden';
      document.getElementById('LiceCat').style.display = 'none';		
			document.getElementById('LeggiCat').style.visibility = 'hidden';
      document.getElementById('LeggiCat').style.display = 'none';		
			//document.getElementById('GastroCat').style.visibility = 'hidden';
      //document.getElementById('GastroCat').style.display = 'none';																			
			document.getElementById('ColCat').style.visibility = 'hidden';
      document.getElementById('ColCat').style.display = 'none';																						
	}