index.html

<!DOCTYPE html>
<html>
  <head>
    <title>Blastar: Save Earth</title>
    <style>
      body {
        margin: 0;
        padding: 0;
        height: 100vh;
        background: #222;
        display: flex;
        justify-content: center;
        align-items: center;
        flex-direction: column;
      }
      canvas {
        border: 1px solid white;
        background: black;
        margin: 100px;
      }
    </style>
  </head>
  <body>
    <div class="game-container">
      <script src="blastar.js"></script>
    </div>
  </body>
</html>