body {
    margin: 0;
    background: #121212;
    color: white;
    font-family: sans-serif;
    display: flex;
    flex-direction: column;
    align-items: center;
  }
  
  canvas {
    background: #222;
    margin-top: 20px;
  }
  
  .knobs {
    margin-top: 20px;
    display: flex;
    gap: 40px;
  }
  
  .knob {
    width: 80px;
    height: 80px;
    background: radial-gradient(circle at 30% 30%, #555, #111);
    border: 4px solid #666;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    user-select: none;
    cursor: ew-resize;
    position: relative;
    box-shadow: 0 0 10px #0ff3;
  }
  
  .knob::after {
    content: '';
    position: absolute;
    width: 6px;
    height: 20px;
    background: #ccc;
    top: 10px;
    left: 50%;
    transform: translateX(-50%);
    border-radius: 3px;
  }
  
  #success, #failure {
    margin-top: 20px;
    font-weight: bold;
    font-size: 1.5em;
    display: none;
  }
  
  #success {
    color: limegreen;
  }
  
  #failure {
    color: red;
  }
  
  #timer {
    margin-top: 10px;
    font-size: 1.2em;
    color: #FFEB3B;
  }