:root {
    --bg: #f6f7f8;
    --card: #ffffff;
    --fg: #18191c;
    --muted: #61666d;
    --line: #e3e5e7;
    --pink: #fb7299;
    --pink-soft: #fff0f4;
    --blue: #00aeec;
    --blue-soft: #e9f8fe;
    --on-pink: #ffffff;
    --radius: 16px;
    --max: 1100px;
  }
  @media (prefers-color-scheme: dark) {
    :root {
      --bg: #0f1012;
      --card: #17181b;
      --fg: #e7e9eb;
      --muted: #9499a0;
      --line: #2a2c30;
      --pink: #ff85ad;
      --pink-soft: #2a1820;
      --blue: #3cc4f5;
      --blue-soft: #10232c;
      --on-pink: #1a0a10;
    }
  }
  * { box-sizing: border-box; }
  html { scroll-behavior: smooth; }
  body {
    margin: 0; background: var(--bg); color: var(--fg);
    font: 16px/1.6 Inter, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
    -webkit-font-smoothing: antialiased; overflow-x: hidden;
  }
  .zh { font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif; }
  a { color: inherit; }
  .wrap { max-width: var(--max); margin: 0 auto; padding: 0 24px; }

  nav { position: sticky; top: 0; z-index: 10; background: color-mix(in srgb, var(--card) 85%, transparent); backdrop-filter: blur(12px); border-bottom: 1px solid var(--line); }
  nav .wrap { display: flex; align-items: center; justify-content: space-between; height: 64px; gap: 16px; }
  .logo { font-weight: 800; letter-spacing: -0.02em; text-decoration: none; font-size: 19px; display: flex; align-items: center; gap: 8px; }
  .logo i { width: 22px; height: 22px; border-radius: 7px; background: linear-gradient(135deg, var(--pink), var(--blue)); display: inline-block; }
  .nav-links { display: flex; gap: 28px; font-size: 15px; color: var(--muted); }
  .nav-links a { text-decoration: none; }
  .nav-links a:hover { color: var(--fg); }

  .btn { display: inline-block; text-decoration: none; font-weight: 600; font-size: 15px; padding: 12px 22px; border-radius: 10px; transition: transform .15s ease, box-shadow .15s ease; white-space: nowrap; }
  .btn:hover { transform: translateY(-1px); }
  .btn-primary { background: var(--pink); color: var(--on-pink); box-shadow: 0 8px 20px -10px var(--pink); }
  .btn-ghost { background: var(--card); color: var(--fg); border: 1px solid var(--line); }
  .btn-sm { padding: 8px 16px; font-size: 14px; }

  section { padding: 96px 0; }
  .band { background: var(--card); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
  .eyebrow { display: inline-block; font-size: 13px; font-weight: 600; color: var(--blue); background: var(--blue-soft); padding: 5px 12px; border-radius: 999px; margin: 0 0 18px; }
  h1 { font-size: clamp(36px, 5.2vw, 58px); line-height: 1.04; letter-spacing: -0.035em; margin: 0 0 22px; font-weight: 800; }
  h1 em { font-style: normal; color: var(--pink); }
  h2 { font-size: clamp(28px, 4vw, 42px); line-height: 1.12; letter-spacing: -0.025em; margin: 0 0 14px; font-weight: 800; }
  h3 { font-size: 18px; margin: 0 0 6px; letter-spacing: -0.01em; }
  .lede { font-size: 19px; color: var(--muted); max-width: 540px; margin: 0 0 32px; }
  .sub { color: var(--muted); max-width: 580px; margin: 0 0 48px; font-size: 17px; }
  .center { text-align: center; }
  .center .sub { margin-left: auto; margin-right: auto; }

  /* hero */
  .hero { position: relative; padding-top: 72px; overflow: hidden; }
  .hero::before, .hero::after { content: ""; position: absolute; border-radius: 50%; filter: blur(80px); opacity: .35; z-index: -1; }
  .hero::before { width: 460px; height: 460px; background: var(--pink); top: -140px; right: -80px; }
  .hero::after { width: 380px; height: 380px; background: var(--blue); bottom: -120px; right: 260px; opacity: .22; }
  .hero-grid { display: grid; grid-template-columns: 1.1fr 1fr; gap: 56px; align-items: center; }
  .cta-row { display: flex; gap: 12px; flex-wrap: wrap; }
  .trust { margin-top: 28px; display: flex; gap: 20px; flex-wrap: wrap; color: var(--muted); font-size: 14px; }
  .trust span::before { content: "✓ "; color: var(--pink); font-weight: 700; }

  /* channel mockup */
  .channel { background: var(--card); border: 1px solid var(--line); border-radius: 20px; padding: 22px; box-shadow: 0 30px 70px -40px rgba(24,25,28,.35); }
  .ch-head { display: flex; align-items: center; gap: 14px; }
  .avatar { width: 56px; height: 56px; border-radius: 50%; background: linear-gradient(135deg, var(--pink), var(--blue)); display: grid; place-items: center; color: #fff; font-weight: 800; font-size: 22px; flex: none; border: 3px solid var(--card); box-shadow: 0 0 0 2px var(--pink); }
  .ch-name { font-weight: 700; font-size: 17px; white-space: nowrap; }
  .ch-name .tag { font-size: 11px; font-weight: 600; color: var(--pink); background: var(--pink-soft); padding: 2px 8px; border-radius: 6px; margin-left: 6px; vertical-align: 2px; }
  .ch-meta { color: var(--muted); font-size: 13px; }
  .follow { white-space: nowrap; margin-left: auto; background: var(--pink); color: var(--on-pink); font-size: 13px; font-weight: 600; padding: 7px 14px; border-radius: 8px; }
  .tiles { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; margin-top: 18px; }
  .tile { aspect-ratio: 16/10; border-radius: 10px; position: relative; overflow: hidden; }
  .tile:nth-child(1) { background: linear-gradient(135deg, #ffd1de, #fb7299); }
  .tile:nth-child(2) { background: linear-gradient(135deg, #c9eefc, #00aeec); }
  .tile:nth-child(3) { background: linear-gradient(135deg, #ffe6c7, #ff9f5a); }
  .tile span { position: absolute; left: 6px; bottom: 5px; font-size: 10px; font-weight: 600; color: #fff; background: rgba(0,0,0,.35); padding: 1px 6px; border-radius: 5px; }
  .ch-rows { margin-top: 16px; display: grid; gap: 10px; }
  .row { display: flex; align-items: center; gap: 12px; padding: 12px 14px; border-radius: 12px; background: var(--bg); font-size: 14px; }
  .row b { margin-left: auto; font-weight: 700; }
  .dot { width: 30px; height: 30px; border-radius: 9px; display: grid; place-items: center; font-size: 15px; flex: none; }
  .dot.p { background: var(--pink-soft); color: var(--pink); }
  .dot.b { background: var(--blue-soft); color: var(--blue); }

  /* services */
  .services { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
  .svc { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 28px; transition: border-color .15s ease, transform .15s ease; }
  .svc:hover { border-color: var(--pink); transform: translateY(-2px); }
  .svc .icon { width: 44px; height: 44px; border-radius: 12px; display: grid; place-items: center; font-size: 20px; margin-bottom: 18px; }
  .svc:nth-child(odd) .icon { background: var(--pink-soft); color: var(--pink); }
  .svc:nth-child(even) .icon { background: var(--blue-soft); color: var(--blue); }
  .svc p { color: var(--muted); margin: 0; font-size: 15px; }

  /* steps */
  .steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; counter-reset: step; }
  .step { background: var(--bg); border-radius: var(--radius); padding: 30px; }
  .step::before { counter-increment: step; content: counter(step); display: grid; place-items: center; width: 34px; height: 34px; border-radius: 50%; background: var(--pink); color: var(--on-pink); font-weight: 700; margin-bottom: 18px; }
  .step p { color: var(--muted); margin: 0; font-size: 15px; }

  /* faq */
  .faq { max-width: 780px; margin: 0 auto; }
  details { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 18px 22px; margin-bottom: 10px; }
  summary { cursor: pointer; font-weight: 600; font-size: 17px; list-style: none; display: flex; justify-content: space-between; gap: 16px; }
  summary::-webkit-details-marker { display: none; }
  summary::after { content: "+"; color: var(--pink); font-weight: 500; font-size: 22px; line-height: 1; }
  details[open] summary::after { content: "–"; }
  details p { color: var(--muted); margin: 10px 0 0; font-size: 15px; }

  /* final */
  .final-card { background: linear-gradient(135deg, var(--pink), #ff9ab8 45%, var(--blue)); color: #fff; border-radius: 24px; padding: 64px 32px; text-align: center; }
  .final-card h2 { color: #fff; }
  .final-card p { color: rgba(255,255,255,.92); max-width: 560px; margin: 0 auto 30px; font-size: 17px; }
  .btn-white { background: #fff; color: #18191c; }

  footer { padding: 32px 0 48px; color: var(--muted); font-size: 14px; }
  footer .wrap { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
  footer .disclaimer { width: 100%; font-size: 12px; margin-top: 8px; }

  .hero-grid > *, .services > *, .steps > * { min-width: 0; }
  h1, h2, .lede { overflow-wrap: anywhere; }

  @media (max-width: 900px) {
    section { padding: 72px 0; }
    .hero-grid { grid-template-columns: 1fr; gap: 44px; }
    .services, .steps { grid-template-columns: 1fr; }
    .nav-links { display: none; }
  }
  @media (max-width: 520px) {
    /* The card header has no room for a button at phone width. */
    .follow, .ch-meta { display: none; }
    .final-card { padding: 48px 22px; }
  }

  .nav-links a.active { color: var(--fg); font-weight: 600; }
  .more { margin-top: 32px; }

  /* ---- online signing ---- */
  [hidden] { display: none !important; }
  .narrow { max-width: 820px; }
  .sub a { color: var(--pink); }
  .sign-steps { display: flex; gap: 10px; flex-wrap: wrap; margin: -16px 0 28px; }
  .sign-steps span { font-size: 14px; font-weight: 600; color: var(--muted); background: var(--card); border: 1px solid var(--line); padding: 6px 14px; border-radius: 999px; }
  .sign-steps b { color: var(--pink); margin-right: 6px; }

  .agreement { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 28px 32px; max-height: 520px; overflow: auto; font-size: 15px; }
  .agreement h3 { font-size: 22px; margin: 0 0 16px; }
  .agreement h4 { font-size: 17px; margin: 26px 0 8px; }
  .agreement p, .agreement li { margin: 0 0 10px; }
  .agreement ul, .agreement ol { padding-left: 22px; margin: 0 0 12px; }
  .agreement hr { border: 0; border-top: 1px solid var(--line); margin: 22px 0; }

  .form-card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 32px; margin-top: 24px; }
  .form-card h3 { font-size: 22px; margin: 0 0 4px; }
  .hint-top { color: var(--muted); margin: 0 0 24px; font-size: 15px; }
  .grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 0 16px; }
  .field { display: grid; gap: 6px; margin-bottom: 18px; min-width: 0; }
  .field label { font-weight: 600; font-size: 14px; }
  .field input { font: inherit; padding: 12px 14px; border-radius: 10px; border: 1px solid var(--line); background: var(--bg); color: var(--fg); width: 100%; }
  .field input:focus { outline: 2px solid var(--pink); outline-offset: 1px; border-color: transparent; }
  .signature input { font-family: "Segoe Script", "Brush Script MT", cursive; font-size: 22px; }
  .check { display: flex; gap: 10px; align-items: flex-start; font-size: 15px; margin-bottom: 12px; cursor: pointer; }
  .check input { margin-top: 3px; width: 18px; height: 18px; flex: none; accent-color: var(--pink); }
  .form-error { color: #d93a5c; font-weight: 600; margin: 4px 0 16px; }
  .privacy { font-size: 13px; color: var(--muted); margin: 16px 0 0; }
  .honey { position: absolute; left: -10000px; width: 1px; height: 1px; overflow: hidden; }
  button.btn { border: 0; cursor: pointer; font-family: inherit; }
  button.btn-ghost { border: 1px solid var(--line); }
  button.btn:disabled { opacity: .6; cursor: default; transform: none; }

  .code-box { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; margin: 4px 0 20px; }
  .code { font: 700 26px/1 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; letter-spacing: .06em; background: var(--pink-soft); color: var(--pink); padding: 14px 18px; border-radius: 12px; }
  .ol-steps { padding-left: 20px; margin: 0 0 20px; color: var(--muted); }
  .ol-steps li { margin-bottom: 8px; }
  .ol-steps strong { color: var(--fg); }
  .signed { display: grid; grid-template-columns: max-content 1fr; gap: 8px 20px; margin: 20px 0 24px; font-size: 15px; }
  .signed dt { color: var(--muted); }
  .signed dd { margin: 0; overflow-wrap: anywhere; }

  .btn-outline-white { background: transparent; color: #fff; border: 1px solid rgba(255,255,255,.75); }
  .final-card .cta-row { justify-content: center; }

  @media (max-width: 600px) {
    .grid-2 { grid-template-columns: 1fr; }
    .agreement { padding: 20px; }
    .form-card { padding: 22px; }
  }
  @media print {
    nav, footer, .no-print { display: none !important; }
    body { background: #fff; color: #000; }
    section { padding: 0; }
    .agreement { max-height: none; overflow: visible; border: 0; padding: 0; }
    .form-card { border: 0; padding: 0; }
  }