index.html

<!DOCTYPE html>
<html>

<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>Open-source Flappy Bird</title>
  <link href="style.css" rel="stylesheet" type="text/css" />
</head>

<style>
  canvas {
    position: absolute;
    top: 30%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 0;
  }

  .playagain {
    position: absolute;
    top: 65%;
    left: 42%;
    background-color: #66b9d4;
    font-size: 40px;
    border-radius: 8px;
    font-family: Verdana, Geneva, Tahoma, sans-serif;
  }
</style>


<body>
  <canvas id="canvas" width="700" height="400" style="border:1px solid #000000" ;></canvas>
  <script src=" script.js"></script><br>
  <button id="playagain" class="playagain" onclick="clickPlayagain()">Play again!</button>
</body>

</html>