ill its container */
  height: 100%;
}
:root {
  --bg-color: #fff;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg-color: #000;
  }
}
canvas {
  background-color: var(--bg-color);
}
    </style>
  </head>
  <body>
    <canvas></canvas>
  </body>
  <script type="module">
import GUI from '../3rdparty/muigui-0.x.module.js';

function createFVertices() {
  const positions = [
    // left column
     -50,  75,  15,
     -20,  75,  15,
     -50, -75,  15,
     -20, -75,  15,

    // top rung
     -20, 