:root {
      --background: #000000;
      --panel: #111111;
      --panel-light: #171717;
      --border: rgba(255, 255, 255, 0.18);
      --text: #ffffff;
      --text-secondary: #cbd5e1;
      --text-muted: #94a3b8;
      --accent: #38bdf8;
      --accent-dark: #0284c7;
    }

    * {
      box-sizing: border-box;
    }

    html {
      scroll-behavior: smooth;
    }

    body {
      margin: 0;
      font-family: Arial, Helvetica, sans-serif;
      background:
        radial-gradient(
          circle at top,
          rgba(56, 189, 248, 0.08),
          transparent 34%
        ),
        var(--background);
      color: var(--text);
      line-height: 1.7;
    }

    .page {
      max-width: 980px;
      margin: 0 auto;
      padding: 42px 22px 64px;
    }

    .back {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      margin-bottom: 28px;
      color: var(--accent);
      text-decoration: none;
      font-weight: 700;
      transition:
        color 0.2s ease,
        transform 0.2s ease;
    }

    .back:hover {
      color: #7dd3fc;
      transform: translateX(-3px);
    }

    .brand {
      margin-bottom: 24px;
    }

    .brand-name {
      margin: 0;
      color: #ffffff;
      font-size: 20px;
      font-weight: 900;
      letter-spacing: 0.4px;
    }

    .brand-subtitle {
      margin: 2px 0 0;
      color: var(--text-muted);
      font-size: 14px;
    }

    .card {
      background:
        linear-gradient(
          145deg,
          rgba(255, 255, 255, 0.055),
          rgba(255, 255, 255, 0.025)
        ),
        var(--panel);
      border: 1px solid var(--border);
      border-radius: 24px;
      padding: 34px;
      box-shadow: 0 24px 60px rgba(0, 0, 0, 0.38);
    }

    h1 {
      color: #ffffff;
      font-size: clamp(34px, 6vw, 46px);
      line-height: 1.15;
      margin: 0 0 8px;
    }

    .updated {
      color: var(--text-muted);
      margin: 0 0 34px;
      font-size: 14px;
    }

    h2 {
      color: #ffffff;
      margin-top: 38px;
      margin-bottom: 12px;
      font-size: 23px;
      line-height: 1.3;
    }

    h2::before {
      content: "";
      display: inline-block;
      width: 4px;
      height: 22px;
      margin-right: 10px;
      border-radius: 10px;
      background: var(--accent);
      vertical-align: -3px;
    }

    h3 {
      color: #ffffff;
      margin-top: 24px;
      margin-bottom: 8px;
      font-size: 18px;
    }

    p,
    li {
      color: var(--text-secondary);
      font-size: 16px;
    }

    p {
      margin: 0 0 16px;
    }

    ul,
    ol {
      padding-left: 24px;
      margin-top: 8px;
    }

    li {
      margin-bottom: 7px;
    }

    a {
      color: var(--accent);
    }

    a:hover {
      color: #7dd3fc;
    }

    .notice {
      margin: 24px 0 8px;
      padding: 18px 20px;
      background: rgba(56, 189, 248, 0.08);
      border: 1px solid rgba(56, 189, 248, 0.28);
      border-radius: 16px;
    }

    .notice p {
      margin: 0;
    }

    .warning {
      margin: 24px 0 8px;
      padding: 18px 20px;
      background: rgba(245, 158, 11, 0.08);
      border: 1px solid rgba(245, 158, 11, 0.28);
      border-radius: 16px;
    }

    .warning p {
      margin: 0;
    }

    .technical-box {
      margin-top: 14px;
      padding: 18px 20px;
      background: var(--panel-light);
      border: 1px solid var(--border);
      border-radius: 16px;
    }

    footer {
      padding: 28px 16px 38px;
      text-align: center;
      color: #64748b;
      font-size: 13px;
    }

    footer a {
      color: var(--accent);
      text-decoration: none;
      margin: 0 9px;
      font-weight: 700;
    }

    .copyright {
      margin-top: 8px;
    }

    @media (max-width: 640px) {
      .page {
        padding: 28px 14px 44px;
      }

      .card {
        padding: 24px 18px;
        border-radius: 20px;
      }

      h2 {
        font-size: 20px;
      }

      p,
      li {
        font-size: 15px;
      }
    }