index.html
<html>
<head>
  <title>Jigsaw</title>
  <link rel='stylesheet' href='styles.css'>
  <script src='library.js'></script>
  <script src='pieces.js'></script>
</head>
<body>
  <div id='grid'>
    <script>pieces();</script>
  </div>
</body>
</html>
styles.css
#grid {
  display:grid;
  width:200px;
  height:200px;
  grid-template-rows: repeat(2,100px);
  grid-template-columns: repeat(2,100px);
}    
.piece {
  grid-row: 1/ span 1;
  grid-column: 1/ span 1;
  width:100%;
  height:100%;
}

On the next page, we'll scramble the pieces so fetch my library from Project 4 so we have the Shuffle function.