/* Base layout ------------------------------------------------------ */
    body {
      margin: 0;
      font-family: system-ui, sans-serif;
      color: #222;
      line-height: 1.5;
    }
    .video-section-header { text-align: center; padding: 2rem 1rem 1rem; }

    /* Sections ---------------------------------------------------------- */
    .video-section {
      max-width: 760px;
      margin: 0 auto 3rem;
      padding: 0 1rem;
    }
    .video-section h2 { margin: 0 0 .5rem; font-size: 1.5rem; }
     .video-section {
      display: block;
      width: 100%;
      max-width: 640px;
      margin: 0 auto 1rem;
      border-radius: 12px;
      box-shadow: 0 4px 12px rgba(0,0,0,.15);
    }
    pre {
      background: #272822;
      color: #f8f8f2;
      padding: .75rem 1rem;
      overflow-x: auto;
      border-radius: 6px;
      font-size: .9rem;
    }
    code { font-family: ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", monospace; }

    /* Simple utility ---------------------------------------------------- */
    .btn {
      display: inline-block;
      margin-top: .5rem;
      padding: .5rem 1rem;
      background: #0366d6;
      color: #fff;
      border: none;
      border-radius: 6px;
      cursor: pointer;
      font-size: 1rem;
    }
    .btn:hover { background: #024fa4; }