<!DOCTYPE html >
<html>
  <head>
    <meta charset="UTF-8"/>

    <link href="./stylesheets/normalize.css" rel="stylesheet" type="text/css"/>
    <link href="./game.css" rel="stylesheet" type="text/css"/>

    <script src="./element-constants.js"></script>
    <script src="./constants.js"></script>
    <script src="./tetrinimo.js"></script>
    <script src="./tetrisBoard.js"></script>
    <script src="./browserView.js"></script>
    <script src="./controller.js"></script>
    <script src="./tetris.js"></script>

    <title>Tetrelementis</title>
  </head>
  <body>
    <main class="container">
      <canvas class="tetris-grid" height="600" width="300">
        Main Game View
      </canvas>
      <canvas class="tetris-preview" height="100" width="100">
        Block Preview
      </canvas>
    </main>
  </body>
</html>

<!DOCTYPE html >
<html>
  <head>
    <meta charset="UTF-8"/>

    <link href="./stylesheets/normalize.css" rel="stylesheet" type="text/css"/>
    <link href="./game.css" rel="stylesheet" type="text/css"/>

    <script src="./element-constants.js"></script>
    <script src="./constants.js"></script>
    <script src="./tetrinimo.js"></script>
    <script src="./tetrisBoard.js"></script>
    <script src="./browserView.js"></script>
    <script src="./controller.js"></script>
    <script src="./tetris.js"></script>

    <title>Tetrelementis</title>
  </head>
  <body>
    <main class="container">
      <canvas id="tetris-grid" height="600" width="300">
        Main Game View
      </canvas>
      <canvas id="tetris-preview" height="100" width="100">
        Block Preview
      </canvas>
    </main>
  </body>
</html>

Update canvas tags to use id's instead of classes
Update canvas tags to use id's instead of classes
