function showDesc(event) {
  var item_ = event.currentTarget.parentNode;
  var items = document.getElementsByClassName('item');
  for (var i = 0, item; item = items[i]; i++) {
    var iframe = item.querySelector('.item_desc');
    if (item == item_ && item.className == 'item') {
      item.className = 'item opened';
      iframe.contentWindow.postMessage('reportHeight', '*');
    } else {
      item.className = 'item';
      iframe.style.height = '0px';
    }
  }
}
Shows description of the news when users clicks on news title.
@param {Object} event Onclick event.