:root {
  --primary: rgb(70,139,223);
  --primary-dark: #2267b6;
  --primary-soft: #eaf4ff;
  --primary-pale: #f4f9ff;
  --ink: #142033;
  --muted: #5f6f86;
  --line: #dbe8f7;
  --card: rgba(255,255,255,.88);
  --shadow: 0 18px 45px rgba(35, 93, 158, .10);
  --radius: 22px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at top left, rgba(70,139,223,.18), transparent 32rem),
    linear-gradient(180deg, #f7fbff 0%, #ffffff 42%, #f4f8fd 100%);
  line-height: 1.75;
  overflow-x: hidden;
}

img {
  max-width: 100%;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

.container {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255,255,255,.86);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid rgba(219,232,247,.8);
}

.header-inner {
  min-height: 70px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  letter-spacing: .02em;
  color: #10253e;
  white-space: nowrap;
}

.logo {
  width: 38px;
  height: 38px;
  border-radius: 12px;
}

.nav-toggle {
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 14px;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
}

.nav-toggle span {
  width: 19px;
  height: 2px;
  background: #16324f;
  border-radius: 999px;
}

.main-nav {
  position: absolute;
  left: 16px;
  right: 16px;
  top: 72px;
  display: none;
  flex-direction: column;
  gap: 6px;
  padding: 14px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 18px;
  box-shadow: var(--shadow);
}

.main-nav.is-open {
  display: flex;
}

.main-nav a {
  padding: 12px 14px;
  border-radius: 12px;
  color: #29415e;
  font-size: 15px;
}

.main-nav a:hover {
  background: var(--primary-soft);
  color: var(--primary-dark);
}

.hero {
  padding: 44px 0 32px;
}

.hero-layout {
  display: grid;
  gap: 30px;
  align-items: center;
}

.hero-copy {
  padding: 6px 0;
}

.eyebrow,
.page-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  width: fit-content;
  padding: 7px 12px;
  border-radius: 999px;
  background: rgba(70,139,223,.11);
  color: var(--primary-dark);
  font-weight: 700;
  font-size: 13px;
  margin-bottom: 16px;
}

h1, h2, h3 {
  line-height: 1.25;
  color: #101f33;
  margin: 0;
}

h1 {
  font-size: clamp(34px, 8vw, 58px);
  letter-spacing: -.04em;
  margin-bottom: 18px;
}

h2 {
  font-size: clamp(26px, 5vw, 38px);
  letter-spacing: -.03em;
  margin-bottom: 14px;
}

h3 {
  font-size: 19px;
  margin-bottom: 10px;
}

p {
  margin: 0 0 14px;
  color: var(--muted);
}

.lead {
  font-size: 17px;
  color: #40536c;
  max-width: 680px;
}

.hero-tags,
.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 18px 0 24px;
}

.hero-tags span,
.tag-row span {
  padding: 8px 11px;
  border-radius: 999px;
  background: #fff;
  border: 1px solid var(--line);
  color: #29435d;
  font-size: 13px;
  box-shadow: 0 8px 22px rgba(70,139,223,.07);
}

.download-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 24px;
  border-radius: 999px;
  background: var(--primary);
  color: #fff;
  font-weight: 800;
  box-shadow: 0 14px 28px rgba(70,139,223,.28);
  transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
  white-space: nowrap;
}

.download-btn:hover {
  transform: translateY(-2px);
  background: var(--primary-dark);
  box-shadow: 0 18px 34px rgba(70,139,223,.34);
}

.hero-visual {
  position: relative;
  min-height: 460px;
  padding: 22px;
  border-radius: 32px;
  overflow: hidden;
  background:
    linear-gradient(145deg, rgba(70,139,223,.18), rgba(255,255,255,.72)),
    radial-gradient(circle at 80% 10%, rgba(70,139,223,.22), transparent 16rem);
  border: 1px solid rgba(255,255,255,.75);
  box-shadow: var(--shadow);
}

.phone-card {
  width: min(280px, 76%);
  margin: 0 auto;
  padding: 14px;
  border-radius: 32px;
  background: rgba(255,255,255,.82);
  border: 1px solid rgba(255,255,255,.9);
  box-shadow: 0 24px 60px rgba(25,67,116,.16);
}

.float-card {
  position: absolute;
  left: 18px;
  right: 18px;
  bottom: 20px;
  padding: 16px;
  border-radius: 18px;
  background: rgba(255,255,255,.9);
  border: 1px solid rgba(219,232,247,.9);
  box-shadow: 0 18px 38px rgba(27,84,147,.13);
}

.float-card strong {
  display: block;
  color: #123151;
  margin-bottom: 6px;
}

.status-dot {
  display: inline-block;
  width: 9px;
  height: 9px;
  margin-right: 7px;
  border-radius: 50%;
  background: #38b76d;
  box-shadow: 0 0 0 5px rgba(56,183,109,.12);
}

.visual-chip {
  position: absolute;
  right: 18px;
  padding: 9px 12px;
  border-radius: 999px;
  background: rgba(255,255,255,.92);
  border: 1px solid var(--line);
  color: #254260;
  font-size: 13px;
  box-shadow: 0 12px 26px rgba(42,91,146,.12);
}

.chip-a { top: 36px; }
.chip-b { top: 86px; }
.chip-c { top: 136px; }

.section {
  padding: 52px 0;
}

.section-head {
  margin-bottom: 24px;
  max-width: 760px;
}

.section-head.center {
  text-align: center;
  margin-left: auto;
  margin-right: auto;
}

.trust-strip {
  display: grid;
  gap: 12px;
  padding: 16px;
  border-radius: 24px;
  background: rgba(255,255,255,.74);
  border: 1px solid rgba(219,232,247,.85);
  box-shadow: var(--shadow);
}

.trust-item {
  padding: 16px;
  border-radius: 18px;
  background: linear-gradient(180deg, #fff, #f5faff);
  border: 1px solid rgba(219,232,247,.75);
}

.trust-item strong {
  display: block;
  color: #123151;
  margin-bottom: 4px;
}

.category-grid,
.feature-grid,
.card-grid,
.scenario-grid {
  display: grid;
  gap: 16px;
}

.category-card,
.feature-card,
.info-card,
.scenario-card,
.faq-item,
.step,
.security-card {
  background: var(--card);
  border: 1px solid rgba(219,232,247,.9);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.category-card,
.feature-card,
.info-card,
.scenario-card {
  padding: 22px;
}

.category-card {
  display: block;
  transition: transform .2s ease, border-color .2s ease;
}

.category-card:hover {
  transform: translateY(-3px);
  border-color: rgba(70,139,223,.45);
}

.category-card span {
  color: var(--primary-dark);
  font-weight: 800;
  font-size: 14px;
}

.category-card p,
.feature-card p,
.info-card p,
.scenario-card p {
  margin-bottom: 0;
}

.split-layout,
.security-layout {
  display: grid;
  gap: 24px;
  align-items: center;
}

.panel {
  padding: 26px;
  border-radius: 28px;
  background: linear-gradient(145deg, #fff, #eef7ff);
  border: 1px solid rgba(219,232,247,.95);
  box-shadow: var(--shadow);
}

.panel-list {
  display: grid;
  gap: 12px;
  margin-top: 18px;
}

.panel-list div {
  padding: 14px;
  border-radius: 16px;
  background: rgba(255,255,255,.82);
  border: 1px solid rgba(219,232,247,.9);
}

.security-panel {
  padding: 24px;
  border-radius: 28px;
  background:
    linear-gradient(160deg, rgba(70,139,223,.14), rgba(255,255,255,.86)),
    radial-gradient(circle at 88% 14%, rgba(70,139,223,.18), transparent 16rem);
  border: 1px solid rgba(219,232,247,.95);
  box-shadow: var(--shadow);
}

.security-card {
  padding: 16px;
  margin-top: 14px;
}

.steps {
  display: grid;
  gap: 14px;
  counter-reset: step;
}

.step {
  position: relative;
  padding: 22px;
}

.step::before {
  counter-increment: step;
  content: counter(step);
  width: 34px;
  height: 34px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 12px;
  background: var(--primary);
  color: #fff;
  font-weight: 800;
  margin-bottom: 12px;
}

.faq-list {
  display: grid;
  gap: 14px;
}

.faq-item {
  padding: 20px;
}

.faq-item h3 {
  font-size: 18px;
}

.cta-section {
  text-align: center;
  padding: 38px 22px;
  border-radius: 30px;
  background:
    linear-gradient(135deg, rgba(70,139,223,.16), rgba(255,255,255,.88)),
    radial-gradient(circle at top right, rgba(70,139,223,.2), transparent 18rem);
  border: 1px solid rgba(219,232,247,.95);
  box-shadow: var(--shadow);
}

.page-hero {
  padding: 44px 0 22px;
}

.page-hero .container {
  display: grid;
  gap: 18px;
}

.content-wrap {
  display: grid;
  gap: 18px;
  padding-bottom: 54px;
}

.article-card {
  padding: 24px;
  border-radius: 24px;
  background: rgba(255,255,255,.88);
  border: 1px solid rgba(219,232,247,.9);
  box-shadow: var(--shadow);
}

.article-card ul,
.article-card ol {
  margin: 12px 0 0;
  padding-left: 20px;
  color: var(--muted);
}

.note-box {
  padding: 18px;
  border-radius: 20px;
  background: #f0f7ff;
  border: 1px solid rgba(70,139,223,.22);
}

.download-area {
  padding: 24px;
  border-radius: 24px;
  background: linear-gradient(135deg, #fff, #f2f8ff);
  border: 1px solid rgba(219,232,247,.9);
  box-shadow: var(--shadow);
  text-align: center;
}

.site-footer {
  padding: 42px 0 20px;
  background: #f0f6fd;
  border-top: 1px solid var(--line);
}

.footer-grid {
  display: grid;
  gap: 26px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
}

.footer-brand img {
  width: 34px;
  height: 34px;
  border-radius: 10px;
}

.site-footer h3 {
  font-size: 16px;
  margin-bottom: 12px;
}

.site-footer a {
  display: block;
  color: #4f6176;
  margin: 7px 0;
}

.footer-bottom {
  margin-top: 28px;
  padding-top: 18px;
  border-top: 1px solid rgba(203,221,239,.8);
  display: flex;
  flex-direction: column;
  gap: 8px;
  color: #6b7a8d;
  font-size: 13px;
}

@media (min-width: 640px) {
  .trust-strip,
  .category-grid,
  .feature-grid,
  .card-grid,
  .scenario-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .nav-toggle {
    display: none;
  }

  .main-nav {
    position: static;
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 4px;
    padding: 0;
    background: transparent;
    border: 0;
    box-shadow: none;
  }

  .main-nav a {
    padding: 9px 12px;
  }

  .hero {
    padding: 70px 0 46px;
  }

  .hero-layout,
  .split-layout,
  .security-layout {
    grid-template-columns: 1fr 1fr;
  }

  .hero-visual {
    min-height: 530px;
  }

  .category-grid,
  .feature-grid,
  .card-grid,
  .scenario-grid,
  .trust-strip {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .trust-strip.four {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .footer-grid {
    grid-template-columns: 1.4fr .8fr .8fr;
  }

  .footer-bottom {
    flex-direction: row;
    justify-content: space-between;
  }
}

@media (max-width: 420px) {
  .container {
    width: min(100% - 24px, 1120px);
  }

  .download-btn {
    width: 100%;
  }

  .hero-visual {
    min-height: 420px;
    padding: 16px;
  }

  .visual-chip {
    position: static;
    display: inline-flex;
    margin: 8px 8px 0 0;
  }

  .float-card {
    left: 16px;
    right: 16px;
  }
}