:root {
  --primary: rgb(70,139,223);
  --primary-dark: #2565b7;
  --primary-soft: #eaf4ff;
  --ink: #11243c;
  --muted: #5d6b7e;
  --line: #d9e6f6;
  --card: rgba(255,255,255,0.92);
  --bg: #f6fbff;
  --shadow: 0 18px 45px rgba(38, 91, 157, 0.12);
  --radius: 22px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
  background: linear-gradient(180deg, #eff7ff 0%, #ffffff 42%, #f6fbff 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: 20;
  background: rgba(255,255,255,0.88);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid rgba(217,230,246,0.8);
}
.header-inner { min-height: 70px; display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; color: #17385f; letter-spacing: .02em; }
.logo { width: 40px; height: 40px; object-fit: contain; }
.nav-toggle { border: 1px solid var(--line); background: #fff; border-radius: 12px; color: var(--primary-dark); font-size: 22px; width: 44px; height: 44px; }
.main-nav { display: none; position: absolute; left: 16px; right: 16px; top: 74px; padding: 12px; border: 1px solid var(--line); border-radius: 18px; background: rgba(255,255,255,0.97); box-shadow: var(--shadow); }
.main-nav.open { display: grid; gap: 4px; }
.main-nav a { padding: 10px 14px; border-radius: 12px; color: #334b68; font-size: 15px; }
.main-nav a.active, .main-nav a:hover { background: var(--primary-soft); color: var(--primary-dark); }
.section { padding: 56px 0; }
.section-tight { padding: 34px 0; }
.eyebrow, .badge { display: inline-flex; align-items: center; gap: 8px; padding: 6px 12px; border-radius: 999px; background: rgba(70,139,223,.1); color: var(--primary-dark); font-weight: 700; font-size: 13px; }
h1, h2, h3 { line-height: 1.25; margin: 0 0 14px; color: var(--ink); }
h1 { font-size: clamp(34px, 8vw, 64px); letter-spacing: -0.04em; }
h2 { font-size: clamp(26px, 5vw, 40px); letter-spacing: -0.03em; }
h3 { font-size: 20px; }
p { margin: 0 0 16px; color: var(--muted); }
.lead { font-size: 18px; color: #40536b; }
.hero { position: relative; padding: 58px 0 46px; overflow: hidden; }
.hero:before { content: ""; position: absolute; inset: -120px -80px auto auto; width: 420px; height: 420px; background: radial-gradient(circle, rgba(70,139,223,.23), transparent 62%); border-radius: 50%; }
.hero-layout { position: relative; display: grid; gap: 28px; align-items: center; }
.hero-copy { max-width: 640px; }
.hero-tags { display: flex; flex-wrap: wrap; gap: 10px; margin: 18px 0 22px; }
.hero-tags span, .pill { display: inline-flex; padding: 8px 12px; border: 1px solid var(--line); background: rgba(255,255,255,.78); border-radius: 999px; color: #37516e; font-size: 13px; font-weight: 700; }
.download-btn { display: inline-flex; align-items: center; justify-content: center; min-height: 48px; padding: 0 22px; border-radius: 999px; background: rgb(70,139,223); color: #fff; font-weight: 800; letter-spacing: .02em; box-shadow: 0 12px 28px rgba(70,139,223,.28); border: 0; cursor: pointer; transition: transform .2s ease, box-shadow .2s ease; }
.download-btn:hover { transform: translateY(-2px); box-shadow: 0 16px 34px rgba(70,139,223,.34); }
.hero-visual { position: relative; min-height: 430px; display: grid; place-items: center; }
.device-card { width: min(340px, 86vw); padding: 18px; border: 1px solid rgba(255,255,255,.72); border-radius: 32px; background: linear-gradient(145deg, rgba(255,255,255,.95), rgba(234,244,255,.78)); box-shadow: var(--shadow); }
.device-card img { border-radius: 26px; margin: auto; }
.float-card { position: absolute; width: 190px; padding: 14px; border-radius: 18px; background: rgba(255,255,255,.92); border: 1px solid var(--line); box-shadow: 0 16px 38px rgba(35, 87, 149, .14); }
.float-card strong { display: block; color: var(--ink); }
.float-card small { color: var(--muted); }
.status-card { top: 18px; left: 0; }
.key-card { right: 0; bottom: 52px; }
.asset-card { left: 8px; bottom: 10px; }
.grid { display: grid; gap: 18px; }
.trust-grid { grid-template-columns: 1fr; }
.trust-item, .card, .faq-item, .category-card, .scenario-card, .step-card, .notice-card {
  background: var(--card);
  border: 1px solid rgba(217,230,246,.92);
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: 0 14px 34px rgba(43, 93, 156, .08);
}
.trust-item strong { display: block; font-size: 18px; margin-bottom: 6px; }
.section-head { max-width: 760px; margin-bottom: 24px; }
.category-grid { grid-template-columns: 1fr; }
.category-card { transition: transform .2s ease, border-color .2s ease; }
.category-card:hover { transform: translateY(-4px); border-color: rgba(70,139,223,.45); }
.category-card .more { color: var(--primary-dark); font-weight: 800; }
.feature-grid { grid-template-columns: 1fr; }
.feature-icon { width: 42px; height: 42px; display: grid; place-items: center; border-radius: 14px; background: var(--primary-soft); color: var(--primary-dark); font-weight: 900; margin-bottom: 12px; }
.split-layout, .security-layout, .guide-layout { display: grid; gap: 24px; align-items: center; }
.panel { border-radius: 28px; padding: 26px; background: linear-gradient(135deg, rgba(70,139,223,.12), rgba(255,255,255,.92)); border: 1px solid var(--line); box-shadow: var(--shadow); }
.panel-list { display: grid; gap: 12px; margin-top: 16px; }
.panel-list div { display: flex; justify-content: space-between; gap: 12px; padding: 12px 14px; border-radius: 14px; background: rgba(255,255,255,.72); color: #3a536f; }
.steps { display: grid; gap: 16px; counter-reset: step; }
.step-card { position: relative; padding-top: 50px; }
.step-card:before { counter-increment: step; content: counter(step); position: absolute; top: 18px; left: 22px; width: 28px; height: 28px; border-radius: 50%; background: var(--primary); color: #fff; display: grid; place-items: center; font-weight: 800; }
.scenario-grid { grid-template-columns: 1fr; }
.faq-list { display: grid; gap: 14px; }
.faq-item h3 { margin-bottom: 8px; }
.cta-section { text-align: center; border-radius: 30px; background: linear-gradient(135deg, #eaf4ff, #ffffff 64%, #eff7ff); border: 1px solid var(--line); padding: 34px 22px; box-shadow: var(--shadow); }
.page-hero { padding: 50px 0 30px; }
.page-hero .container { display: grid; gap: 20px; }
.content-wrap { display: grid; gap: 20px; }
.article-card { background: rgba(255,255,255,.94); border: 1px solid var(--line); border-radius: 28px; padding: 24px; box-shadow: var(--shadow); }
.article-card ul, .article-card ol { color: var(--muted); padding-left: 20px; }
.info-grid { display: grid; gap: 16px; }
.callout { padding: 18px; border-left: 4px solid var(--primary); background: var(--primary-soft); border-radius: 16px; color: #35516e; }
.download-panel { display: grid; gap: 16px; justify-items: start; }
.only-download { text-align: center; justify-items: center; }
.site-footer { margin-top: 56px; padding: 44px 0 24px; background: #eef6ff; border-top: 1px solid var(--line); }
.footer-grid { display: grid; gap: 22px; }
.footer-brand { display: inline-flex; align-items: center; gap: 10px; margin-bottom: 10px; }
.footer-brand img { width: 32px; height: 32px; }
.site-footer h3 { font-size: 16px; margin-bottom: 10px; }
.site-footer a { display: block; color: #45617f; margin: 6px 0; }
.footer-bottom { display: flex; flex-direction: column; gap: 8px; margin-top: 28px; padding-top: 18px; border-top: 1px solid rgba(190,211,235,.8); color: #5e7087; font-size: 13px; }
@media (min-width: 640px) {
  .trust-grid, .category-grid, .info-grid, .scenario-grid { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 900px) {
  .nav-toggle { display: none; }
  .main-nav { position: static; display: flex; align-items: center; gap: 4px; padding: 0; border: 0; background: transparent; box-shadow: none; }
  .hero { padding: 76px 0 70px; }
  .hero-layout { grid-template-columns: 1.05fr .95fr; }
  .feature-grid, .category-grid { grid-template-columns: repeat(3, 1fr); }
  .trust-grid { grid-template-columns: repeat(4, 1fr); }
  .split-layout, .security-layout, .guide-layout { grid-template-columns: 1fr 1fr; }
  .steps { grid-template-columns: repeat(4, 1fr); }
  .scenario-grid { grid-template-columns: repeat(3, 1fr); }
  .footer-grid { grid-template-columns: 2fr 1fr 1fr 1fr; }
  .footer-bottom { flex-direction: row; justify-content: space-between; }
  .article-card { padding: 34px; }
}
@media (max-width: 460px) {
  .container { width: min(100% - 24px, 1120px); }
  .float-card { position: static; width: 100%; margin-top: 10px; }
  .hero-visual { min-height: auto; display: block; }
  .device-card { width: 100%; }
  .download-btn { width: 100%; }
}