function hideMenus() {
  var d = document.getElementsByTagName('div');
  for (var i = 0; i < d.length; i++) {
    if (d[i].className == 'submenu') {
      if (d[i].style.display == 'block')
        d[i].style.display = 'none';
    }
  }
}

function handleMenu(id) {
  var d = document.getElementsByTagName('div');
  for (var i = 0; i < d.length; i++) {
    if (d[i].className == 'submenu' && d[i] != document.getElementById(id)) {
      if (d[i].style.display == 'block')
        d[i].style.display = 'none';
    }
  }
  if (document.getElementById(id).style.display != 'block')
    document.getElementById(id).style.display = 'block';
  else
    document.getElementById(id).style.display = 'none';
}