function changeDisplay(id) {
  var element = document.getElementById(id);
  var display_block_value = 'block';
  var display_none_value = 'none';
  if (element != null)
  {
    if(element.style.display == display_block_value)
    {
      element.style.display = display_none_value;
    } 
    else 
    {
      element.style.display = display_block_value;
    }
  }
}

function closeDisplay(id) {
  var element = document.getElementById(id);
  var display_none_value = 'none';
  if (element != null)
  {
    element.style.display = display_none_value;
  }
}

function komentarz(form) {
	document.getElementById(form).style.display = 'block';
	return false;
}
function komentarzSchowaj(form) {
	document.getElementById(form).style.display = 'none';
	return false;
}