    body {
      text-align: center;
      font-family: Verdana, Geneva, sans-serif;
    }

    canvas {
      border: 1px solid;
      background-color: greenyellow;
    }

    #wrapper {
      width: 1000px;
      margin: auto;
    }

    .controlPanel {
      margin-bottom: 10px;
    }

    input[type="number"] {
      width: 50px;
    }