/* Dark mode */
    body {
      background-color: #1f1f1f;
      color: #f0f0f0;
      margin: 0;
      font-family: sans-serif;
      user-select: none;
    }
    .container {
      width: 90%;
      max-width: 1000px;
      margin: 0 auto;
      padding: 1em;
    }
    h1 {
      text-align: center;
      margin: 0.5em 0;
    }

    .control-panel {
      display: flex;
      flex-direction: column;
      gap: 0.8em;
      margin-bottom: 1em;
      padding: 1em;
      background-color: #2c2c2c;
      border-radius: 5px;
    }
    .control-row {
      display: flex;
      align-items: center;
      gap: 0.5em;
      margin-bottom: 0.3em;
    }
    .control-row label {
      flex-shrink: 0;
      width: 240px;
      text-align: right;
    }
    .control-row input[type="range"] {
      flex-grow: 1;
    }
    .control-row .value-label {
      width: 100px;
      text-align: right;
      flex-shrink: 0;
    }
    .radio-group {
      width: auto;
      text-align: left;
    }
    .radio-group label {
      margin-right: 1em;
    }

    .playback-buttons {
      display: flex;
      gap: 1em;
      justify-content: center;
      margin-bottom: 1em;
    }
    button {
      background-color: #444;
      color: #fff;
      border: 1px solid #666;
      border-radius: 4px;
      padding: 0.5em 1em;
      cursor: pointer;
      font-size: 18px;
    }
    button:hover {
      background-color: #555;
    }
    button:active {
      background-color: #666;
    }
    button#playBtn {
      background-color: #080;
      border: 1px solid #040;
    }
    button#playBtn:hover {
      background-color: #0a0;
    }
    button#playBtn:active {
      background-color: #0c0;
    }

    button#stopBtn {
      background-color: #800;
      border: 1px solid #400;
    }
    button#stopBtn:hover {
      background-color: #a00;
    }
    button#stopBtn:active {
      background-color: #c00;
    }

    .graph-container {
      display: flex;
      flex-direction: column;
      gap: 1em;
    }
    .graph {
      position: relative;
      background-color: #2c2c2c;
      border: 1px solid #444;
      height: 300px;
      width: 100%;
    }
    .graph canvas {
      position: absolute;
      left: 0;
      top: 0;
    }