body {
      margin: 0;
      min-height: 100vh;
      display: grid;
      place-items: center;
      background: #0d0f12;
      color: #e8eaed;
      font: 16px Arial, sans-serif;
    }

    .panel {
      width: min(680px, 90%);
      padding: 28px;
      background: #171a1f;
      border: 1px solid #30353d;
      border-radius: 12px;
      box-sizing: border-box;
    }

    h1 {
      margin: 0 0 8px;
      font-size: 30px;
    }

    .version {
      color: #8ab4f8;
      margin-bottom: 24px;
    }

    .feature {
      padding: 14px;
      margin: 10px 0;
      background: #20242a;
      border-radius: 8px;
    }

    .structure {
      margin-top: 8px;
      padding: 12px;
      background: #0b0d10;
      border-radius: 8px;
      border: 1px solid #30353d;
      font-size: 12px;
    }

    .timer {
      margin-top: 24px;
      padding: 18px;
      text-align: center;
      background: #0b0d10;
      border-radius: 8px;
      border: 1px solid #30353d;
    }

    .time {
      display: block;
      margin-top: 8px;
      font: 700 28px monospace;
      color: #7ee787;
    }

    .footer {
      margin-top: 24px;
      color: #8b949e;
      font-size: 14px;
    }