diff --git a/index.html b/index.html
index 9386faaf4..5bb4a8f63 100644
--- a/index.html
+++ b/index.html
@@ -5,12 +5,13 @@
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
     <meta http-equiv="X-UA-Compatible" content="ie=edge" />
     <title>Superhero Memory Game</title>
-    <!-- LINK THE STYLES HERE -->
+    <link rel="style.css" href="/styles/style.css">
   </head>
   <body>
     <div>
       <h1>Superhero Memory Game</h1>
     </div>
+    <button id="restart-button" onClick="startGame()">Reiniciar jogo</button>
     <div id="score">
       <h2>Score</h2>
       <p>Pairs clicked: <span id="pairs-clicked">0</span></p>
@@ -18,6 +19,7 @@ <h2>Score</h2>
     </div>
     <div id="memory-board"></div>
 
-    <!-- LINK THE JAVASCRIPT FILES HERE (keep in mind that the order in which you link them MATTERS) -->
+    <script src="src/memory.js"></script>
+    <script src="src/index.js"></script>
   </body>
 </html>
diff --git a/src/memory.js b/src/memory.js
index f6644827e..a0ca48c8e 100644
--- a/src/memory.js
+++ b/src/memory.js
@@ -1,18 +1,34 @@
 class MemoryGame {
+
   constructor(cards) {
     this.cards = cards;
     // add the rest of the class properties here
+    this.pickedCards = [];
+    this.pairsClicked = 0;
+    this.pairsGuessed = 0;
   }
 
   shuffleCards() {
-    // ... write your code here
+
+    if (!this.cards || !Array.isArray(this.cards)) {
+      return undefined;
+    }
+    this.cards.sort(() => Math.random() - 0.5);
+    return this.cards;
   }
 
   checkIfPair(card1, card2) {
-    // ... write your code here
+
+    this.pairsClicked++;
+
+    if (card1 === card2) {
+      this.pairsGuessed++
+      return true;
+    }
+    return false;
   }
 
   checkIfFinished() {
-    // ... write your code here
+    return this.pairsGuessed === (this.cards.length / 2);
   }
 }
