function toggle(e)
{
  var l = e.parentNode.childNodes;
  for (var i in l)
    if (l[i].className == 'htc')
    {
      if (l[i].style.display == 'block')
        l[i].style.display = 'none';
      else
        l[i].style.display = 'block';
      return;
    }
}