body {
    margin: 0;
    background: black;
    overflow: hidden;
    font-family: Arial, sans-serif;
  }
  #gameCanvas {
    display: block;
    margin: 0 auto;
    background: #000;
  }
  #score {
    position: absolute;
    top: 10px;
    left: 10px;
    color: #fff;
    font-size: 20px;
    font-family: Arial, sans-serif;
  }
  #gameOver {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: #fff;
    font-size: 36px;
    display: none;
    text-align: center;
    background: rgba(0,0,0,0.8);
    padding: 20px;
    border-radius: 10px;
  }
  button {
    margin-top: 10px;
    padding: 10px 20px;
    font-size: 16px;
    cursor: pointer;
  }