Помогите со скриптом

function setCookie(name, value, expiredays, path, domain, secure) {
    if (expiredays) {
       var exdate=new Date();
       exdate.setDate(exdate.getDate()+expiredays);
       var expires = exdate.toGMTString();
    }
    document.cookie = name + "=" + escape(value) +
    ((expiredays) ? "; expires=" + expires : "") +
    ((path) ? "; path=" + path : "") +
    ((domain) ? "; domain=" + domain : "") +
    ((secure) ? "; secure" : "");
}

function getCookie(name) {
  var cookie = " " + document.cookie;
  var search = " " + name + "=";
  var setStr = null;
  var offset = 0;
  var end = 0;
  if (cookie.length > 0) {
   offset = cookie.indexOf(search);
   if (offset != -1) {
    offset += search.length;
    end = cookie.indexOf(";", offset)
    if (end == -1) {
     end = cookie.length;
    }
    setStr = unescape(cookie.substring(offset, end));
   }
  }
  return(setStr);
}

function deleteCookie(nameCo)  
{
var exp3 = new Date();
exp3.setTime (exp3.getTime() - 1000000000);
var cval = getCookie(nameCo);
document.cookie = nameCo + "=" + cval + "; expires=" + exp.toGMTString();
}

<script type="text/javascript">
(function() {  
  var textHolder = document.getElementsByClassName('big-text-neon')[0],
    text = textHolder.innerHTML,
   chars = text.length,
   newText = '',
   i;  

  for (i = 0; i < chars; i += 1) {
   newText += '<em>' + text.charAt(i) + '</em>';
  }

  textHolder.innerHTML = newText;

  var letters = document.getElementsByTagName('em'),
   flickers = [5, 7, 9, 11, 13, 15, 17],
   randomLetter,
   flickerNumber,
   counter;

  function randomFromInterval(from,to) {
   return Math.floor(Math.random()*(to-from+1)+from);
  }

  function hasClass(element, cls) {
   return (' ' + element.className + ' ').indexOf(' ' + cls + ' ') > -1;
  }

  function flicker() {   
   counter += 1;
    
   if (counter === flickerNumber) {
    return;
   }

   setTimeout(function () {
    if(hasClass(randomLetter, 'off')) {
     randomLetter.className = '';
    }
    else {
     randomLetter.className = 'off';
    }

    flicker();
   }, 30);
  }

  (function loop() {
   var rand = randomFromInterval(300,1200);

   randomLetter = randomFromInterval(0, 6);
   randomLetter = letters[randomLetter];
    
   flickerNumber = randomFromInterval(0, 3);
   flickerNumber = flickers[flickerNumber];

   setTimeout(function() {
     counter = 0;
     flicker();
     loop();   
   }, rand);
  }());
})(jQuery);
</script>