function navigazione_veloce(){
  var pagina = document.getElementById('navigazione_veloce').value;
  location.href = pagina;
  return false;
}

function toggle_menu(divId, cl){
  var div = document.getElementById(divId);
  if (hasCSSClass(div, cl)) removeCSSClass(div, cl);
  else addCSSClass(div, cl);
}

function hasCSSClass(div, n){
  classes = div.className.split(" ");
  for (var i=0; i<classes.length; i++){
    if (classes[i] == n) return true;
  }
  return false;
}

function addCSSClass(div, n){
  removeCSSClass(div, n);
  div.className += " "+n;
}

function removeCSSClass(div, n){
  classes = div.className.split(" ");
  className = "";
  for (var i=0; i<classes.length; i++){
    if (classes[i] != n) className += classes[i] + " ";
  }
  div.className = ""+className;
}