:root {
  --primary: rgb(70,139,223);
  --primary-dark: #245fba;
  --primary-soft: #eaf3ff;
  --ink: #142238;
  --muted: #64748b;
  --line: #dbe7f7;
  --surface: #ffffff;
  --surface-blue: #f5f9ff;
  --shadow: 0 18px 48px rgba(45, 99, 170, .12);
  --radius: 22px;
  --radius-sm: 16px;
}

* { 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(--ink);
  background:
    radial-gradient(circle at top left, rgba(70,139,223,.18), transparent 34rem),
    linear-gradient(180deg, #f7fbff 0%, #ffffff 42%, #f4f8ff 100%);
  line-height: 1.72;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
.container { width: min(100% - 32px, 1160px); margin: 0 auto; }
.section { padding: 56px 0; }
.section-tight { padding: 36px 0; }
.section-title { margin: 0 0 12px; font-size: clamp(26px, 4vw, 42px); line-height: 1.2; letter-spacing: -0.03em; }
.section-desc { margin: 0 0 28px; color: var(--muted); max-width: 760px; }
.kicker, .badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 12px;
  border: 1px solid rgba(70,139,223,.2);
  color: var(--primary-dark);
  background: rgba(255,255,255,.72);
  border-radius: 999px;
  font-weight: 700;
  font-size: 13px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,.82);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(219,231,247,.8);
}
.header-inner { min-height: 72px; 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: -0.02em; }
.logo { width: 38px; height: 38px; border-radius: 12px; }
.brand-text { font-size: 19px; }
.nav-toggle {
  width: 44px; height: 44px; border: 1px solid var(--line); border-radius: 14px;
  background: #fff; display: inline-grid; place-items: center; gap: 4px; padding: 10px;
}
.nav-toggle span { display: block; width: 18px; height: 2px; background: var(--ink); border-radius: 999px; }
.site-nav {
  position: absolute;
  left: 16px; right: 16px; top: 74px;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: #fff;
  box-shadow: var(--shadow);
  display: none;
  grid-template-columns: 1fr;
  gap: 6px;
}
.site-nav.is-open { display: grid; }
.site-nav a { padding: 11px 12px; border-radius: 12px; color: #334155; font-weight: 700; }
.site-nav a.active, .site-nav a:hover { background: var(--primary-soft); color: var(--primary-dark); }

.hero { padding: 54px 0 32px; }
.hero-layout { display: grid; gap: 34px; align-items: center; }
.hero h1 { margin: 14px 0 16px; font-size: clamp(34px, 8vw, 68px); line-height: 1.03; letter-spacing: -0.055em; }
.hero p { color: #496276; font-size: 17px; margin: 0 0 20px; }
.hero-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; margin-top: 22px; }
.hero-tags { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 20px; }
.hero-tags span { padding: 8px 12px; border: 1px solid var(--line); border-radius: 999px; background: rgba(255,255,255,.78); color: #2f4f72; font-weight: 700; font-size: 13px; }
.download-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 22px;
  border-radius: 999px;
  background: var(--primary);
  color: #fff;
  font-weight: 800;
  letter-spacing: .02em;
  box-shadow: 0 14px 26px rgba(70,139,223,.25);
  border: 0;
  cursor: pointer;
  transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
}
.download-btn:hover { transform: translateY(-2px); background: var(--primary-dark); box-shadow: 0 18px 32px rgba(70,139,223,.28); }
.download-note { color: var(--muted); font-size: 13px; }
.hero-visual {
  position: relative;
  min-height: 430px;
  border-radius: 30px;
  background: linear-gradient(145deg, rgba(70,139,223,.16), rgba(255,255,255,.88));
  border: 1px solid rgba(70,139,223,.16);
  padding: 24px;
  overflow: hidden;
  box-shadow: var(--shadow);
}
.hero-visual:before {
  content: "";
  position: absolute; inset: 30px 24px auto auto;
  width: 210px; height: 210px; border-radius: 50%;
  background: rgba(70,139,223,.12); filter: blur(10px);
}
.app-shot { width: min(72%, 320px); margin: 8px auto 0; filter: drop-shadow(0 20px 36px rgba(22,61,116,.18)); }
.float-card, .status-card {
  position: absolute;
  background: rgba(255,255,255,.9);
  border: 1px solid rgba(219,231,247,.88);
  border-radius: 18px;
  box-shadow: 0 16px 30px rgba(40, 79, 140, .10);
  padding: 14px;
}
.status-card { left: 18px; bottom: 22px; width: 190px; }
.status-card strong { display: block; font-size: 15px; }
.status-card span { color: var(--muted); font-size: 12px; }
.float-card { right: 14px; font-size: 13px; font-weight: 800; color: #264766; }
.float-card.one { top: 44px; }
.float-card.two { top: 118px; }
.float-card.three { bottom: 82px; }
.pulse { width: 10px; height: 10px; display: inline-block; border-radius: 50%; background: #28b981; box-shadow: 0 0 0 7px rgba(40,185,129,.12); margin-right: 8px; }

.trust-strip { display: grid; grid-template-columns: 1fr; gap: 12px; }
.trust-item {
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: rgba(255,255,255,.78);
}
.trust-item strong { display: block; font-size: 17px; margin-bottom: 4px; }
.trust-item span { color: var(--muted); font-size: 14px; }

.category-grid, .feature-grid, .scenario-grid, .article-grid, .faq-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}
.category-card, .feature-card, .scenario-card, .info-card, .faq-item, .article-card, .step-card, .tip-card {
  border: 1px solid rgba(219,231,247,.9);
  background: rgba(255,255,255,.86);
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: 0 10px 30px rgba(26,75,140,.07);
}
.category-card { position: relative; overflow: hidden; min-height: 164px; }
.category-card:after { content: ""; position: absolute; width: 92px; height: 92px; right: -30px; bottom: -32px; background: rgba(70,139,223,.12); border-radius: 50%; }
.category-card h3, .feature-card h3, .scenario-card h3, .article-card h3 { margin: 0 0 8px; font-size: 20px; }
.category-card p, .feature-card p, .scenario-card p, .article-card p, .info-card p, .tip-card p { color: var(--muted); margin: 0; }
.card-link { display: inline-flex; margin-top: 14px; color: var(--primary-dark); font-weight: 800; }
.icon-badge { 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: 14px; }

.split-layout, .security-layout, .page-layout { display: grid; gap: 22px; align-items: center; }
.panel-gradient {
  border-radius: 28px;
  border: 1px solid rgba(70,139,223,.18);
  background: linear-gradient(145deg, rgba(70,139,223,.12), rgba(255,255,255,.9));
  padding: 24px;
  box-shadow: var(--shadow);
}
.security-stack { display: grid; gap: 12px; }
.security-row { display: flex; gap: 12px; align-items: flex-start; padding: 16px; border-radius: 16px; background: #fff; border: 1px solid var(--line); }
.security-row b { color: var(--primary-dark); }
.security-row p { margin: 2px 0 0; color: var(--muted); font-size: 14px; }

.steps { display: grid; gap: 14px; counter-reset: step; }
.step-card { position: relative; padding-left: 78px; min-height: 112px; }
.step-card:before {
  counter-increment: step;
  content: counter(step);
  position: absolute; left: 22px; top: 22px;
  width: 38px; height: 38px; border-radius: 14px;
  background: var(--primary); color: #fff; display: grid; place-items: center; font-weight: 900;
}
.step-card h3 { margin: 0 0 6px; }
.step-card p { margin: 0; color: var(--muted); }

.cta-section {
  text-align: center;
  border-radius: 30px;
  border: 1px solid rgba(70,139,223,.16);
  background: linear-gradient(135deg, rgba(70,139,223,.12), rgba(255,255,255,.92));
  padding: 42px 20px;
  box-shadow: var(--shadow);
}
.cta-section h2 { margin: 0 0 12px; font-size: clamp(26px, 5vw, 40px); }
.cta-section p { margin: 0 auto 22px; color: var(--muted); max-width: 680px; }

.page-hero { padding: 48px 0 24px; }
.page-hero .page-title { margin: 14px 0 14px; font-size: clamp(32px, 7vw, 58px); line-height: 1.08; letter-spacing: -0.04em; max-width: 900px; }
.page-hero p { color: var(--muted); max-width: 820px; margin: 0 0 22px; font-size: 17px; }
.article-content { display: grid; gap: 18px; }
.article-content h2 { margin: 0 0 8px; font-size: 24px; }
.article-content p { margin: 0 0 12px; color: #42566f; }
.check-list { margin: 0; padding: 0; list-style: none; display: grid; gap: 10px; }
.check-list li { padding: 12px 14px; background: #fff; border: 1px solid var(--line); border-radius: 14px; color: #42566f; }
.check-list li:before { content: "✓"; color: var(--primary-dark); font-weight: 900; margin-right: 8px; }
.warning-list li:before { content: "!"; }
.faq-item h3 { margin: 0 0 8px; font-size: 18px; }
.faq-item p { margin: 0; color: var(--muted); }
.download-card { max-width: 760px; margin: 0 auto; text-align: center; }

.site-footer { margin-top: 36px; padding: 42px 0 20px; background: #eef6ff; border-top: 1px solid var(--line); }
.footer-grid { display: grid; gap: 24px; }
.footer-brand { display: inline-flex; align-items: center; gap: 10px; margin-bottom: 8px; }
.footer-brand img { width: 34px; height: 34px; border-radius: 10px; }
.site-footer p { color: var(--muted); margin: 0; }
.site-footer h3 { margin: 0 0 10px; font-size: 16px; }
.site-footer a { display: block; color: #42566f; padding: 4px 0; }
.footer-bottom { margin-top: 26px; padding-top: 18px; border-top: 1px solid rgba(70,139,223,.16); color: var(--muted); display: grid; gap: 8px; font-size: 13px; }

@media (min-width: 680px) {
  .category-grid, .feature-grid, .scenario-grid, .article-grid, .faq-grid { grid-template-columns: repeat(2, 1fr); }
  .trust-strip { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1.3fr 1fr 1fr 1fr; }
}

@media (min-width: 980px) {
  .container { width: min(100% - 56px, 1160px); }
  .nav-toggle { display: none; }
  .site-nav { position: static; display: flex; align-items: center; gap: 4px; padding: 0; border: 0; box-shadow: none; background: transparent; }
  .site-nav a { padding: 9px 13px; }
  .hero { padding: 72px 0 44px; }
  .hero-layout { grid-template-columns: 1.03fr .97fr; gap: 56px; }
  .trust-strip { grid-template-columns: repeat(4, 1fr); }
  .category-grid, .feature-grid, .scenario-grid { grid-template-columns: repeat(3, 1fr); }
  .faq-grid { grid-template-columns: repeat(2, 1fr); }
  .split-layout, .security-layout, .page-layout { grid-template-columns: 1fr 1fr; gap: 42px; }
  .steps { grid-template-columns: repeat(4, 1fr); }
  .step-card { padding-left: 22px; padding-top: 76px; }
  .step-card:before { top: 22px; left: 22px; }
}

@media (min-width: 1180px) {
  .article-grid.four { grid-template-columns: repeat(4, 1fr); }
}

@media (max-width: 380px) {
  .container { width: min(100% - 24px, 1160px); }
  .hero-visual { padding: 16px; min-height: 390px; }
  .float-card { right: 8px; }
  .status-card { left: 10px; width: 168px; }
  .download-btn { width: 100%; }
}