function kadabra(zap) 
{
  if (document.getElementById) 
  {
    var abra = document.getElementById(zap).style;
    if (abra.display != "none") 
    {
      abra.display = "none";
    } 
    else 
    {
      abra.display = "block"
    }
    return false
  } 
  else 
  {
    return true
  }
}