functions.js

		var myCards = document.getElementById('container');
		var resultsArray = [];
		var counter = 0;
		var text = document.getElementById('text');
		var seconds = 00; 
		var tens = 00; 
		var appendTens = document.getElementById("tens");
		var appendSeconds = document.getElementById("seconds");
		var Interval ;
		var images = [
		  'queen', 
		  'king', 
		  'jack', 
		  'ace', 
		  'joker'
		];

		var clone = images.slice(0); // duplicate array
		var cards = images.concat(clone); // merge to arrays 

		// Shufffel function
		function shuffle(o){
		  for(var j, x, i = o.length; i; j = Math.floor(Math.random() * i), x = o[--i],   o[i] = o[j], o[j] = x);
		  return o;
		}
		shuffle(cards);

		for (var i = 0; i < cards.length; i++) {
		  card = document.createElement('div');
		  card.dataset.item = cards[i];
		  card.dataset.view = "card";
		  myCards.appendChild(card);
		     
		  card.onclick = function () {
		   
		    if (this.className != 'flipped' && this.className != 'correct'){
		        this.className = 'flipped';
		        var result = this.dataset.item;
		        resultsArray.push(result);
		        clearInterval(Interval);
		        Interval = setInterval(startTimer, 10);
		    }
		  
		    if (resultsArray.length > 1) {

		      if (resultsArray[0] === resultsArray[1]) {
		        check("correct");
		        counter ++;
		        win();
		        resultsArray = [];
		      } else {
		        check("reverse");
		        resultsArray = [];
		      }
		      
		    }
		    
		  }
		   
		};


		var check = function(className) {
		  
		  var x = document.getElementsByClassName("flipped");
		  setTimeout(function() {

		    for(var i = (x.length - 1); i >= 0; i--) {
		      x[i].className = className;
		    }
		     
		  },500);
		   
		}

		var win = function () {

		  if(counter === 5) {
		    clearInterval(Interval);
		    text.innerHTML = "Parabéns! Seu tempo foi de " + seconds + ":" + tens;
		  } 
		  
		}
		     
		function startTimer () {
		  tens++; 
		    
		  if(tens < 9){
		    appendTens.innerHTML = "0" + tens;
		  }
		    
		  if (tens > 9){
		    appendTens.innerHTML = tens;
		      
		  } 
		    
		  if (tens > 99) {
		    seconds++;
		    appendSeconds.innerHTML = "0" + seconds;
		    tens = 0;
		    appendTens.innerHTML = "0" + 0;
		  }
		    
		  if (seconds > 9){
		    appendSeconds.innerHTML = seconds;
		  }
		  
		}