function popup()
{
  document.getElementById('popup').style.display = 'block';
}

function close_popup()
{
  document.getElementById('popup').style.display = 'none';
}

function send_message()
{
  var form = document.getElementById('feedback_form');
  // validate fields
  if( !form.name.value || form.name.value == '' )
  {
    alert('Укажите Ваше имя');
    return;
  }
  if( !form.email.value || form.email.value == '' )
  {
    alert('Укажите адрес электронной почты');
    return;
  }
  if( !form.text.value || form.text.value == '' )
  {
    alert('Заполните поле сообщения');
    return;
  }

  var params = 'name='+form.name.value+'&email='+form.email.value+'&theme='+form.theme.value+'&text='+form.text.value;
  var loader = new net.ContentLoader('feedback',
                                    update_popup,
                                    null,
                                    'POST',
                                    params);
}

function update_popup()
{
  document.getElementById('feedback_more').style.display = 'block';
}

function more_feedback()
{
  var form = document.getElementById('feedback_form');
  form.name.value = '';
  form.email.value = '';
  form.theme.value = '';
  form.text.value = '';

  document.getElementById('feedback_more').style.display = 'none';
}