:root {
      --bg: #070b12;
      --bg-2: #0c1420;
      --panel: #101a28;
      --panel-2: #152233;
      --line: rgba(94, 210, 255, 0.14);
      --line-strong: rgba(94, 210, 255, 0.28);
      --cyan: #3ec7ff;
      --cyan-2: #1aa6e0;
      --mint: #3dffc5;
      --text: #e8f2ff;
      --muted: #8aa0b8;
      --max: 1140px;
      --nav-h: 64px;
      --font-display: "DIN Alternate", "Segoe UI", "PingFang SC", "Microsoft YaHei UI", sans-serif;
      --font-body: "Segoe UI", "PingFang SC", "Microsoft YaHei UI", "Noto Sans SC", sans-serif;
      --font-mono: "Cascadia Mono", "Consolas", "SF Mono", ui-monospace, monospace;
    }

    * { box-sizing: border-box; }
    html { scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-h) + 12px); }
    body {
      margin: 0;
      color: var(--text);
      font-family: var(--font-body);
      background: var(--bg);
      line-height: 1.65;
      -webkit-font-smoothing: antialiased;
    }
    a { color: inherit; text-decoration: none; }
    .wrap { width: min(100% - 2.4rem, var(--max)); margin-inline: auto; }

    /* —— 顶部导航 —— */
    .site-nav {
      position: fixed;
      inset: 0 0 auto;
      z-index: 50;
      height: var(--nav-h);
      display: flex;
      align-items: center;
      background: rgba(7, 11, 18, 0.82);
      backdrop-filter: blur(14px) saturate(1.2);
      border-bottom: 1px solid var(--line);
    }
    .site-nav::after {
      content: "";
      position: absolute;
      left: 0; right: 0; bottom: -1px;
      height: 1px;
      background: linear-gradient(90deg, transparent, rgba(62, 199, 255, 0.55), transparent);
      pointer-events: none;
    }
    .nav-inner {
      width: min(100% - 2.4rem, var(--max));
      margin-inline: auto;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 1rem;
    }
    .nav-brand {
      display: inline-flex;
      align-items: center;
      gap: 0.65rem;
      min-width: 0;
    }
    .nav-logo {
      width: 1.7rem;
      height: 1.7rem;
      object-fit: contain;
      display: block;
      flex: 0 0 auto;
    }
    .nav-brand strong {
      font-family: var(--font-display);
      font-size: 1.05rem;
      letter-spacing: 0.12em;
      font-weight: 700;
      white-space: nowrap;
    }
    .nav-brand span {
      color: var(--muted);
      font-size: 0.75rem;
      letter-spacing: 0.08em;
      white-space: nowrap;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 0.15rem 1.15rem;
      margin: 0;
      padding: 0;
      list-style: none;
      font-size: 0.9rem;
      color: var(--muted);
      letter-spacing: 0.06em;
    }
    .nav-links a {
      position: relative;
      padding: 0.35rem 0;
      transition: color 0.2s ease;
    }
    .nav-links a:hover { color: var(--text); }
    .nav-links a::after {
      content: "";
      position: absolute;
      left: 0; right: 0; bottom: 0;
      height: 1px;
      background: var(--cyan);
      transform: scaleX(0);
      transform-origin: left;
      transition: transform 0.22s ease;
    }
    .nav-links a:hover::after { transform: scaleX(1); }
    .nav-links .home-link {
      color: var(--cyan);
      font-family: var(--font-mono);
      font-size: 0.82rem;
    }
    .nav-links .home-link::before {
      content: "← ";
      opacity: 0.75;
    }
    .nav-cta {
      display: inline-flex;
      align-items: center;
      min-height: 2.35rem;
      padding: 0 0.95rem;
      border: 1px solid var(--cyan);
      background: linear-gradient(180deg, rgba(62, 199, 255, 0.18), rgba(62, 199, 255, 0.05));
      color: var(--text);
      font-size: 0.86rem;
      font-weight: 650;
      letter-spacing: 0.08em;
      clip-path: polygon(8px 0, 100% 0, 100% calc(100% - 8px), calc(100% - 8px) 100%, 0 100%, 0 8px);
      transition: background 0.2s ease, transform 0.2s ease;
    }
    .nav-cta:hover {
      background: linear-gradient(180deg, rgba(62, 199, 255, 0.32), rgba(62, 199, 255, 0.1));
      transform: translateY(-1px);
    }
    .nav-toggle {
      display: none;
      width: 2.4rem;
      height: 2.4rem;
      border: 1px solid var(--line-strong);
      background: transparent;
      color: var(--text);
      cursor: pointer;
      padding: 0;
    }
    .nav-toggle span {
      display: block;
      width: 1.1rem;
      height: 1px;
      margin: 0.28rem auto;
      background: var(--cyan);
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      min-height: 3rem;
      padding: 0.7rem 1.35rem;
      border: 1px solid transparent;
      font: inherit;
      font-weight: 650;
      letter-spacing: 0.08em;
      cursor: pointer;
      clip-path: polygon(10px 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%, 0 10px);
      transition: transform 0.2s ease, background 0.2s ease, border-color 0.2s ease;
    }
    .btn-primary {
      background: linear-gradient(135deg, #2bb8ef, #1a8fc4 55%, #157aab);
      color: #041018;
      border-color: rgba(62, 199, 255, 0.5);
      box-shadow: 0 0 0 1px rgba(62, 199, 255, 0.15), 0 12px 30px rgba(26, 143, 196, 0.28);
    }
    .btn-primary:hover { transform: translateY(-2px); filter: brightness(1.06); }
    .btn-ghost {
      background: rgba(62, 199, 255, 0.04);
      color: var(--text);
      border-color: var(--line-strong);
    }
    .btn-ghost:hover { background: rgba(62, 199, 255, 0.1); border-color: var(--cyan); }

    /* —— Hero —— */
    .hero {
      position: relative;
      min-height: 100vh;
      min-height: 100dvh;
      padding-top: var(--nav-h);
      overflow: hidden;
      background:
        radial-gradient(ellipse 55% 45% at 82% 22%, rgba(62, 199, 255, 0.16), transparent 60%),
        radial-gradient(ellipse 40% 35% at 12% 78%, rgba(61, 255, 197, 0.08), transparent 55%),
        linear-gradient(165deg, #05080f 0%, #0a1220 48%, #0d1830 100%);
    }
    .hero::before {
      content: "";
      position: absolute;
      inset: 0;
      background-image:
        linear-gradient(rgba(62, 199, 255, 0.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(62, 199, 255, 0.05) 1px, transparent 1px);
      background-size: 56px 56px;
      mask-image: radial-gradient(ellipse 75% 65% at 55% 40%, #000 15%, transparent 75%);
      animation: grid-move 24s linear infinite;
      pointer-events: none;
    }
    .hero::after {
      content: "";
      position: absolute;
      inset: 0;
      background: repeating-linear-gradient(
        0deg,
        transparent,
        transparent 2px,
        rgba(0, 0, 0, 0.08) 2px,
        rgba(0, 0, 0, 0.08) 3px
      );
      opacity: 0.35;
      pointer-events: none;
    }
    @keyframes grid-move {
      from { transform: translateY(0); }
      to { transform: translateY(56px); }
    }
    @keyframes rise {
      from { opacity: 0; transform: translateY(18px); }
      to { opacity: 1; transform: translateY(0); }
    }
    @keyframes pulse-line {
      0%, 100% { opacity: 0.35; }
      50% { opacity: 0.9; }
    }

    .hero-grid {
      position: relative;
      z-index: 1;
      display: grid;
      grid-template-columns: 1.05fr 1fr;
      gap: clamp(1.8rem, 4vw, 3.2rem);
      align-items: center;
      min-height: calc(100vh - var(--nav-h));
      min-height: calc(100dvh - var(--nav-h));
      padding: clamp(2.5rem, 7vh, 4rem) 0;
    }
    .hero-copy { animation: rise 0.8s ease both; max-width: 34rem; }
    .chip {
      display: inline-flex;
      align-items: center;
      gap: 0.45rem;
      margin-bottom: 1rem;
      padding: 0.28rem 0.7rem;
      border: 1px solid var(--line-strong);
      background: rgba(62, 199, 255, 0.06);
      color: var(--cyan);
      font-family: var(--font-mono);
      font-size: 0.75rem;
      letter-spacing: 0.08em;
    }
    .chip i {
      width: 0.4rem;
      height: 0.4rem;
      border-radius: 50%;
      background: var(--mint);
      box-shadow: 0 0 8px rgba(61, 255, 197, 0.7);
      animation: pulse-line 2.2s ease-in-out infinite;
    }
    .brand {
      margin: 0 0 0.85rem;
      font-family: var(--font-display);
      font-size: clamp(2.5rem, 6vw, 4.3rem);
      font-weight: 750;
      letter-spacing: 0.12em;
      line-height: 1.05;
      background: linear-gradient(120deg, #f2f8ff 20%, #3ec7ff 70%, #3dffc5 110%);
      -webkit-background-clip: text;
      background-clip: text;
      color: transparent;
    }
    .headline {
      margin: 0 0 0.8rem;
      font-size: clamp(1.05rem, 2vw, 1.35rem);
      font-weight: 500;
      letter-spacing: 0.08em;
      color: #c9ddf2;
    }
    .lead {
      margin: 0 0 1.6rem;
      color: var(--muted);
      font-size: 0.98rem;
      max-width: 32em;
    }
    .cta-row { display: flex; flex-wrap: wrap; gap: 0.75rem; }
    .risk {
      margin: 1rem 0 0;
      font-family: var(--font-mono);
      font-size: 0.78rem;
      color: rgba(138, 160, 184, 0.85);
      letter-spacing: 0.04em;
    }

    .hero-visual { animation: rise 0.95s ease 0.08s both; }
    .ui-shell {
      position: relative;
      border: 1px solid var(--line-strong);
      background: linear-gradient(180deg, #121e2e, #0c1522);
      box-shadow:
        0 0 0 1px rgba(62, 199, 255, 0.05),
        0 28px 70px rgba(0, 0, 0, 0.45);
      overflow: hidden;
    }
    .ui-shell::before {
      content: "";
      position: absolute;
      inset: 0 auto 0 0;
      width: 2px;
      background: linear-gradient(180deg, transparent, var(--cyan), var(--mint), transparent);
      opacity: 0.8;
    }
    .ui-titlebar {
      display: flex;
      align-items: center;
      gap: 0.55rem;
      padding: 0.7rem 0.9rem;
      background: rgba(8, 14, 24, 0.95);
      border-bottom: 1px solid var(--line);
      font-family: var(--font-mono);
      font-size: 0.75rem;
      color: var(--muted);
      letter-spacing: 0.04em;
    }
    .ui-dots { display: flex; gap: 0.35rem; }
    .ui-dots span {
      width: 0.5rem; height: 0.5rem; border-radius: 50%;
      background: rgba(138, 160, 184, 0.35);
    }
    .ui-dots span:nth-child(1) { background: #ff6b6b; }
    .ui-dots span:nth-child(2) { background: #f0c36a; }
    .ui-dots span:nth-child(3) { background: #3dffc5; }
    .ui-body { display: grid; grid-template-columns: 7.4rem 1fr; min-height: 290px; }
    .ui-side {
      padding: 0.85rem 0.55rem;
      background: #0a121d;
      border-right: 1px solid var(--line);
      font-size: 0.72rem;
      color: var(--muted);
    }
    .ui-side div {
      padding: 0.45rem 0.5rem;
      margin-bottom: 0.2rem;
      border: 1px solid transparent;
    }
    .ui-side .on {
      color: var(--cyan);
      background: rgba(62, 199, 255, 0.08);
      border-color: rgba(62, 199, 255, 0.2);
    }
    .ui-main { padding: 0.85rem; }
    .ui-toolbar { display: flex; gap: 0.4rem; margin-bottom: 0.75rem; }
    .ui-chip {
      padding: 0.28rem 0.55rem;
      font-size: 0.68rem;
      letter-spacing: 0.04em;
      background: rgba(62, 199, 255, 0.18);
      color: var(--cyan);
      border: 1px solid rgba(62, 199, 255, 0.3);
    }
    .ui-chip.dim {
      background: rgba(255, 255, 255, 0.03);
      color: var(--muted);
      border-color: var(--line);
    }
    .ui-table { width: 100%; border-collapse: collapse; font-size: 0.72rem; }
    .ui-table th {
      text-align: left;
      color: rgba(138, 160, 184, 0.7);
      font-weight: 500;
      padding: 0.35rem 0.4rem;
      border-bottom: 1px solid var(--line);
      font-family: var(--font-mono);
    }
    .ui-table td {
      padding: 0.5rem 0.4rem;
      color: #d7e6f7;
      border-bottom: 1px solid rgba(94, 210, 255, 0.06);
    }
    .tag {
      display: inline-block;
      padding: 0.1rem 0.4rem;
      font-size: 0.65rem;
      border: 1px solid rgba(61, 255, 197, 0.35);
      color: var(--mint);
      background: rgba(61, 255, 197, 0.08);
    }
    .tag.warn {
      border-color: rgba(240, 195, 106, 0.4);
      color: #f0c36a;
      background: rgba(240, 195, 106, 0.08);
    }

    .trust {
      border-block: 1px solid var(--line);
      background: rgba(16, 26, 40, 0.75);
      padding: 1.15rem 0;
    }
    .trust-row {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 1rem;
      text-align: center;
      font-size: 0.9rem;
      color: var(--muted);
    }
    .trust-row strong {
      display: block;
      margin-bottom: 0.2rem;
      color: var(--cyan);
      font-family: var(--font-mono);
      font-size: 0.82rem;
      letter-spacing: 0.1em;
      font-weight: 600;
    }

    section { padding: clamp(3.4rem, 7vw, 5.2rem) 0; }
    .section-kicker {
      margin: 0 0 0.45rem;
      color: var(--cyan);
      font-family: var(--font-mono);
      font-size: 0.78rem;
      letter-spacing: 0.16em;
    }
    .section-title {
      margin: 0 0 0.7rem;
      font-family: var(--font-display);
      font-size: clamp(1.5rem, 3vw, 2.05rem);
      letter-spacing: 0.08em;
    }
    .section-desc {
      margin: 0 0 2rem;
      max-width: 38em;
      color: var(--muted);
    }

    .outcomes { background: var(--bg-2); }
    .outcome-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 1rem;
    }
    .outcome {
      padding: 1.35rem 1.2rem;
      border: 1px solid var(--line);
      background:
        linear-gradient(180deg, rgba(62, 199, 255, 0.05), transparent 40%),
        var(--panel);
    }
    .outcome h3 {
      margin: 0 0 0.45rem;
      font-size: 1.05rem;
      letter-spacing: 0.06em;
    }
    .outcome p { margin: 0; color: var(--muted); font-size: 0.94rem; }

    .flow {
      background: var(--bg);
      border-block: 1px solid var(--line);
    }
    .flow-track {
      display: grid;
      grid-template-columns: repeat(5, 1fr);
      gap: 0.75rem;
      counter-reset: step;
    }
    .flow-item {
      padding: 1rem 0.85rem;
      border: 1px solid var(--line);
      background: var(--panel);
      position: relative;
    }
    .flow-item::before {
      counter-increment: step;
      content: counter(step, decimal-leading-zero);
      display: block;
      margin-bottom: 0.5rem;
      font-family: var(--font-mono);
      font-size: 0.9rem;
      color: var(--cyan);
      letter-spacing: 0.1em;
    }
    .flow-item h3 { margin: 0 0 0.3rem; font-size: 0.98rem; letter-spacing: 0.05em; }
    .flow-item p { margin: 0; color: var(--muted); font-size: 0.88rem; }

    .features { background: var(--bg-2); }
    .feature-list { list-style: none; margin: 0; padding: 0; }
    .feature-list li {
      display: grid;
      grid-template-columns: minmax(7rem, 10rem) 1fr;
      gap: 1.2rem;
      padding: 1.25rem 0;
      border-top: 1px solid var(--line);
      align-items: baseline;
    }
    .feature-list li:last-child { border-bottom: 1px solid var(--line); }
    .feature-list h3 {
      margin: 0;
      color: var(--cyan);
      font-family: var(--font-mono);
      font-size: 0.92rem;
      letter-spacing: 0.06em;
      font-weight: 600;
    }
    .feature-list p { margin: 0; color: var(--muted); }

    .download {
      position: relative;
      overflow: hidden;
      background:
        radial-gradient(ellipse 55% 70% at 100% 0%, rgba(62, 199, 255, 0.14), transparent 55%),
        linear-gradient(135deg, #0b1524, #08101a);
      border-top: 1px solid var(--line);
    }
    .download-box {
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      justify-content: space-between;
      gap: 1.2rem;
    }
    .download-meta,
    .download-hint {
      width: 100%;
      margin: 0;
      color: var(--muted);
      font-size: 0.92rem;
    }
    .download-activate {
      width: 100%;
      margin: 0;
    }
    .download-activate a[hidden],
    .download-meta[hidden],
    .download-hint[hidden] {
      display: none;
    }
    .tips {
      margin: 1.4rem 0 0;
      padding: 0;
      list-style: none;
      display: grid;
      grid-template-columns: repeat(2, minmax(0, 1fr));
      gap: 0.45rem 1.4rem;
      color: var(--muted);
      font-size: 0.92rem;
    }
    .tips li {
      position: relative;
      padding-left: 1rem;
    }
    .tips li::before {
      content: "";
      position: absolute;
      left: 0;
      top: 0.72em;
      width: 0.35rem;
      height: 0.35rem;
      background: var(--mint);
      box-shadow: 0 0 8px rgba(61, 255, 197, 0.5);
    }

    footer {
      padding: 2rem 0 2.6rem;
      border-top: 1px solid var(--line);
      background: #05080f;
      color: var(--muted);
      font-size: 0.88rem;
    }
    footer strong {
      color: var(--text);
      font-family: var(--font-display);
      letter-spacing: 0.12em;
    }
    footer p { margin: 0.3rem 0; }
    .full-name { color: #c5d7ea; }
    footer a:hover { color: var(--cyan); }

    .sticky-dl {
      display: none;
      position: fixed;
      left: 0; right: 0; bottom: 0;
      z-index: 40;
      padding: 0.75rem 1rem calc(0.75rem + env(safe-area-inset-bottom));
      background: rgba(7, 11, 18, 0.94);
      border-top: 1px solid var(--line);
      backdrop-filter: blur(10px);
    }
    .sticky-dl .btn { width: 100%; }

    @media (max-width: 960px) {
      .hero-grid { grid-template-columns: 1fr; min-height: auto; }
      .hero-visual { order: -1; margin-top: 0.5rem; }
      .outcome-grid { grid-template-columns: 1fr; }
      .flow-track { grid-template-columns: 1fr 1fr; }
      .trust-row { grid-template-columns: 1fr 1fr; }
      .nav-links, .nav-cta { display: none; }
      .nav-toggle { display: inline-block; }
      .site-nav.is-open .nav-links {
        display: flex;
        position: absolute;
        top: var(--nav-h);
        left: 0; right: 0;
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        padding: 0.5rem 1.2rem 1rem;
        background: rgba(7, 11, 18, 0.96);
        border-bottom: 1px solid var(--line);
      }
      .site-nav.is-open .nav-links a {
        padding: 0.85rem 0;
        border-bottom: 1px solid var(--line);
      }
      .site-nav.is-open .nav-cta {
        display: inline-flex;
        position: absolute;
        top: calc(var(--nav-h) + 14.5rem);
        right: 1.2rem;
        left: 1.2rem;
        justify-content: center;
      }
    }
    @media (max-width: 640px) {
      .wrap, .nav-inner { width: min(100% - 1.35rem, var(--max)); }
      .nav-brand span { display: none; }
      .ui-body { grid-template-columns: 1fr; }
      .ui-side { display: none; }
      .feature-list li { grid-template-columns: 1fr; gap: 0.35rem; }
      .flow-track { grid-template-columns: 1fr; }
      .tips { grid-template-columns: 1fr; }
      .cta-row { flex-direction: column; align-items: stretch; }
      .btn { width: 100%; }
      .sticky-dl { display: block; }
      body { padding-bottom: 4.6rem; }
    }
    @media (prefers-reduced-motion: reduce) {
      .hero::before, .hero-copy, .hero-visual, .chip i { animation: none; }
      .btn, .nav-cta { transition: none; }
    }