:root {
  --primary: rgb(70,139,223);
  --primary-dark: rgb(42, 92, 168);
  --primary-soft: rgba(70,139,223,.12);
  --bg: #f4f8ff;
  --surface: #ffffff;
  --surface-blue: #eef6ff;
  --text: #17213a;
  --muted: #64748b;
  --line: rgba(70, 139, 223, .18);
  --shadow: 0 18px 45px rgba(27, 70, 128, .10);
  --radius: 22px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(70,139,223,.18), transparent 34rem),
    linear-gradient(180deg, #f8fbff 0%, #eef6ff 45%, #ffffff 100%);
  line-height: 1.75;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
.container { width: min(1120px, calc(100% - 32px)); margin: 0 auto; }
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, .86);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid var(--line);
}
.nav-container { width: min(1120px, calc(100% - 24px)); margin: 0 auto; min-height: 68px; display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; letter-spacing: .02em; }
.logo-img { width: 38px; height: 38px; border-radius: 12px; box-shadow: 0 10px 26px rgba(70,139,223,.18); }
.brand-text { font-size: 18px; }
.nav-toggle { border: 1px solid var(--line); background: #fff; color: var(--primary-dark); border-radius: 14px; width: 42px; height: 42px; font-size: 22px; }
.site-nav { position: absolute; left: 12px; right: 12px; top: 72px; display: none; flex-direction: column; gap: 6px; padding: 12px; border-radius: 18px; background: rgba(255,255,255,.98); border: 1px solid var(--line); box-shadow: var(--shadow); }
.site-nav.is-open { display: flex; }
.site-nav a { padding: 10px 12px; border-radius: 12px; color: #334155; font-size: 15px; }
.site-nav a:hover { background: var(--primary-soft); color: var(--primary-dark); }
.hero { padding: 46px 0 28px; }
.hero-layout { display: grid; gap: 28px; align-items: center; }
.eyebrow, .badge { display: inline-flex; align-items: center; width: fit-content; gap: 7px; padding: 7px 12px; border-radius: 999px; color: var(--primary-dark); background: rgba(70,139,223,.10); border: 1px solid var(--line); font-size: 13px; font-weight: 700; }
h1 { margin: 18px 0 12px; font-size: clamp(30px, 8vw, 56px); line-height: 1.12; letter-spacing: -.04em; }
.page-hero h1 { font-size: clamp(28px, 7vw, 48px); }
.lead { font-size: 17px; color: #48576d; margin: 0 0 22px; max-width: 660px; }
.hero-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; margin-top: 22px; }
.download-btn { display: inline-flex; align-items: center; justify-content: center; min-height: 48px; padding: 12px 22px; border-radius: 999px; background: linear-gradient(135deg, var(--primary), #65a5f1); color: #fff; font-weight: 800; box-shadow: 0 14px 28px rgba(70,139,223,.28); border: 0; cursor: pointer; transition: transform .18s ease, box-shadow .18s ease; }
.download-btn:hover { transform: translateY(-2px); box-shadow: 0 18px 36px rgba(70,139,223,.34); }
.text-link { color: var(--primary-dark); font-weight: 700; }
.hero-visual { position: relative; min-height: 420px; display: grid; place-items: center; padding: 18px; }
.device-card { width: min(390px, 92vw); border-radius: 34px; padding: 18px; background: linear-gradient(150deg, rgba(255,255,255,.95), rgba(238,246,255,.72)); border: 1px solid rgba(255,255,255,.9); box-shadow: var(--shadow); }
.device-card img { border-radius: 26px; margin: 0 auto; }
.float-card { position: absolute; background: rgba(255,255,255,.92); border: 1px solid var(--line); border-radius: 18px; padding: 12px 14px; box-shadow: 0 16px 35px rgba(27, 70, 128, .10); font-size: 13px; color: #334155; }
.float-card strong { display: block; color: var(--text); }
.float-card.status { top: 28px; left: 6px; }
.float-card.key { bottom: 70px; left: 0; }
.float-card.verify { top: 112px; right: 0; }
.float-card.protect { bottom: 16px; right: 18px; }
.section { padding: 48px 0; }
.section-title { max-width: 760px; margin-bottom: 24px; }
.section-title h2, .content-block h2 { margin: 0 0 10px; font-size: clamp(24px, 5vw, 38px); line-height: 1.2; letter-spacing: -.02em; }
.section-title p, .content-block p, .page-content p { color: var(--muted); margin: 0 0 14px; }
.trust-grid, .feature-grid, .category-grid, .scenario-grid, .article-grid { display: grid; gap: 16px; }
.trust-card, .feature-card, .category-card, .scenario-card, .info-card, .faq-item, .step, .article-card, .notice-card {
  background: rgba(255,255,255,.88);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: 0 14px 36px rgba(27, 70, 128, .07);
}
.trust-card strong { display: block; color: var(--primary-dark); font-size: 18px; margin-bottom: 4px; }
.trust-card span, .feature-card p, .category-card p, .scenario-card p, .step p, .article-card p, .notice-card p { color: var(--muted); margin: 0; }
.category-card { transition: transform .18s ease, border-color .18s ease; }
.category-card:hover { transform: translateY(-3px); border-color: rgba(70,139,223,.42); }
.category-card h3, .feature-card h3, .scenario-card h3, .article-card h3, .notice-card h3 { margin: 0 0 8px; font-size: 19px; }
.category-card .card-link, .article-card .card-link { display: inline-flex; margin-top: 14px; color: var(--primary-dark); font-weight: 800; }
.split-layout, .security-layout { display: grid; gap: 24px; align-items: center; }
.panel-blue { background: linear-gradient(145deg, rgba(70,139,223,.10), rgba(255,255,255,.88)); border: 1px solid var(--line); border-radius: 28px; padding: 24px; box-shadow: var(--shadow); }
.panel-list { display: grid; gap: 12px; padding: 0; margin: 16px 0 0; list-style: none; }
.panel-list li { display: flex; gap: 10px; align-items: flex-start; color: #40506a; }
.panel-list li::before { content: ""; width: 9px; height: 9px; margin-top: 10px; border-radius: 50%; background: var(--primary); flex: 0 0 auto; }
.steps { display: grid; gap: 14px; counter-reset: step; }
.step { position: relative; padding-top: 52px; }
.step::before { counter-increment: step; content: counter(step); position: absolute; top: 18px; left: 20px; width: 30px; height: 30px; border-radius: 10px; display: grid; place-items: center; color: #fff; background: var(--primary); font-weight: 800; }
.cta-section { text-align: center; border-radius: 30px; padding: 34px 20px; background: linear-gradient(135deg, rgba(70,139,223,.13), rgba(255,255,255,.94)); border: 1px solid var(--line); box-shadow: var(--shadow); }
.cta-section h2 { margin: 0 0 10px; font-size: clamp(24px, 5vw, 38px); }
.cta-section p { color: var(--muted); max-width: 720px; margin: 0 auto 22px; }
.faq-list { display: grid; gap: 14px; }
.faq-item h3 { margin: 0 0 8px; font-size: 18px; }
.faq-item p { margin: 0; color: var(--muted); }
.page-hero { padding: 44px 0 24px; }
.page-card-layout { display: grid; gap: 18px; align-items: start; }
.page-content { background: rgba(255,255,255,.82); border: 1px solid var(--line); border-radius: 28px; padding: 24px; box-shadow: var(--shadow); }
.page-content h2 { margin: 24px 0 10px; font-size: 24px; }
.guide-steps { display: grid; gap: 12px; margin: 18px 0; }
.guide-step { display: grid; grid-template-columns: 38px 1fr; gap: 12px; align-items: start; }
.guide-step span { width: 38px; height: 38px; border-radius: 13px; background: var(--primary-soft); color: var(--primary-dark); display: grid; place-items: center; font-weight: 900; }
.guide-step strong { display: block; margin-bottom: 4px; }
.guide-step p { margin: 0; }
.warning-list { margin: 18px 0; padding: 0; list-style: none; display: grid; gap: 10px; }
.warning-list li { padding: 12px 14px; border-radius: 16px; background: #f6faff; border: 1px solid var(--line); color: #42526b; }
.download-single { margin-top: 24px; }
.download-page-card { text-align: center; max-width: 780px; margin: 0 auto; }
.only-download-wrap { margin: 24px 0; display: flex; justify-content: center; }
.site-footer { margin-top: 48px; background: #f7fbff; border-top: 1px solid var(--line); padding: 36px 0 20px; color: #475569; }
.footer-grid { display: grid; gap: 24px; }
.footer-brand { display: flex; align-items: center; gap: 10px; color: var(--text); }
.footer-brand img { width: 34px; height: 34px; border-radius: 11px; }
.site-footer h3 { margin: 0 0 10px; color: var(--text); font-size: 16px; }
.site-footer a { display: block; margin: 7px 0; color: #52627a; }
.footer-bottom { width: min(1120px, calc(100% - 32px)); margin: 24px auto 0; padding-top: 18px; border-top: 1px solid var(--line); font-size: 13px; color: #718096; }
@media (min-width: 640px) {
  .trust-grid, .category-grid, .article-grid { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .page-content { padding: 30px; }
}
@media (min-width: 880px) {
  .nav-toggle { display: none; }
  .site-nav { position: static; display: flex; flex-direction: row; align-items: center; gap: 4px; padding: 0; border: 0; box-shadow: none; background: transparent; }
  .hero { padding: 72px 0 44px; }
  .hero-layout, .split-layout, .security-layout, .page-card-layout { grid-template-columns: 1.02fr .98fr; }
  .hero-visual { min-height: 500px; }
  .trust-grid { grid-template-columns: repeat(4, 1fr); }
  .category-grid, .feature-grid, .scenario-grid, .article-grid { grid-template-columns: repeat(3, 1fr); }
  .steps { grid-template-columns: repeat(4, 1fr); }
  .footer-grid { grid-template-columns: 2fr 1fr 1fr; }
  .section { padding: 66px 0; }
  .page-hero { padding: 64px 0 30px; }
}