:root {
  --ink: #12324a;
  --ink-soft: #5a7a90;
  --paper: #eef7ff;
  --surface: #ffffff;
  --line: #cfe5f7;
  --accent: #0ea5e9;
  --accent-hover: #0284c7;
  --accent-deep: #0369a1;
  --glow: #38bdf8;
  --gutter: 4vw;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(1200px 420px at 12% -10%, rgba(56, 189, 248, 0.28), transparent 60%),
    radial-gradient(900px 360px at 88% 0%, rgba(14, 165, 233, 0.16), transparent 55%),
    linear-gradient(180deg, #f7fbff 0%, var(--paper) 40%, #f3f9ff 100%);
  font: 16px/1.7 "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  padding-bottom: 160px;
}
a { color: var(--accent); text-underline-offset: 3px; }
a:hover { color: var(--accent-hover); }
.skip { position: absolute; left: -999px; }
.skip:focus { left: 16px; top: 12px; background: #fff; padding: 8px 12px; }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.wrap {
  width: min(1080px, calc(100% - 48px));
  max-width: 1080px;
  padding-left: 0;
  padding-right: 0;
  box-sizing: border-box;
  margin: 0 auto;
}

.site-header {
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
  box-shadow: 0 8px 24px rgba(14, 165, 233, 0.06);
  position: sticky;
  top: 0;
  z-index: 20;
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  width: min(1080px, calc(100% - 48px));
  margin: 0 auto;
  padding: 16px 0;
  box-sizing: border-box;
}
.brand {
  display: flex;
  flex-direction: column;
  text-decoration: none;
  color: inherit;
}
.brand-en {
  font-size: 12px;
  letter-spacing: 0.34em;
  color: var(--accent);
}
.brand-zh {
  font-size: 30px;
  line-height: 1.2;
  font-weight: 700;
  letter-spacing: 0.04em;
}
.brand-sub { font-size: 13px; color: var(--ink-soft); margin-top: 4px; }
.nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 4px 16px;
  font-size: 14px;
}
.nav a {
  color: var(--ink);
  text-decoration: none;
  padding-bottom: 4px;
  border-bottom: 1px solid transparent;
}
.nav a:hover, .nav a[aria-current="page"] {
  color: var(--accent);
  border-bottom-color: var(--accent);
}
.nav-toggle {
  display: none;
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--line);
  padding: 6px 12px;
  cursor: pointer;
}

.hero {
  padding: 48px 0 8px;
}
.hero h1,
.page-hero h1 {
  margin: 0 0 16px;
  font-size: clamp(36px, 3.6vw, 52px);
  line-height: 1.15;
  letter-spacing: -0.03em;
  font-weight: 650;
}
.kicker {
  font-size: 12px;
  letter-spacing: 0.22em;
  color: var(--accent);
  margin: 0 0 12px;
}
.answer-box {
  font-size: 18px;
  line-height: 1.75;
  background: linear-gradient(90deg, #f0f9ff 0%, #ffffff 55%);
  border: 1px solid var(--line);
  border-left: 4px solid var(--accent);
  box-shadow: 0 10px 28px rgba(14, 165, 233, 0.08);
  padding: 22px 24px;
  margin: 0 0 20px;
  max-width: none;
}
.meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  color: var(--ink-soft);
  font-size: 13px;
  margin: 0 0 22px;
}
.stats-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin: 8px 0 12px;
}
.hero-side {
  display: grid;
  gap: 14px;
}
.stat {
  background: linear-gradient(180deg, #ffffff 0%, #f5fbff 100%);
  border: 1px solid var(--line);
  border-top: 3px solid var(--accent);
  box-shadow: 0 8px 20px rgba(14, 165, 233, 0.07);
  padding: 22px 22px 18px;
}
.stat b {
  display: block;
  font-size: 28px;
  line-height: 1.2;
  color: var(--ink);
  letter-spacing: -0.02em;
}
.stat span { color: var(--ink-soft); font-size: 14px; }

.page-hero {
  padding: 40px 0 8px;
}
.crumbs {
  font-size: 13px;
  color: var(--ink-soft);
  margin: 18px 0 0;
}
.crumbs a { color: inherit; text-decoration: none; }
.crumbs a:hover { color: var(--accent); }

.section { padding: 28px 0 8px; }
.section h2 {
  margin: 0 0 14px;
  font-size: 22px;
  font-weight: 650;
}
.section-head {
  display: grid;
  grid-template-columns: 160px minmax(0, 1fr) auto;
  gap: 16px 28px;
  align-items: end;
  margin-bottom: 22px;
}
.section-head h2 {
  margin: 0;
  font-size: clamp(24px, 2.2vw, 32px);
  letter-spacing: -0.02em;
}
.num {
  color: var(--accent);
  font-size: 13px;
  letter-spacing: 0.16em;
  display: block;
  padding-bottom: 6px;
}
.section-head .more {
  color: var(--ink-soft);
  text-decoration: none;
  font-size: 14px;
}
.section-head .more:hover { color: var(--accent); }

.grid-3, .grid-2, .cards, .faq { display: grid; gap: 18px; }
.grid-3, .cards.grid-3, .faq { grid-template-columns: repeat(3, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.card {
  background: var(--surface);
  border: 1px solid var(--line);
  padding: 22px 22px 18px;
  min-height: 140px;
}
.product-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 22px;
}
.product-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  box-shadow: 0 12px 28px rgba(14, 165, 233, 0.08);
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}
.product-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 16px 34px rgba(14, 165, 233, 0.14);
}
.product-card img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  display: block;
  background: #eef1f4;
}
.product-card-body { padding: 16px 18px 18px; }
.product-card-body h3 { margin: 0 0 8px; font-size: 20px; }
.product-card-body p { margin: 0; color: var(--ink-soft); }
.product-detail {
  display: grid;
  grid-template-columns: minmax(280px, 0.9fr) minmax(0, 1.1fr);
  gap: 28px 40px;
  align-items: start;
  padding: 36px 0 12px;
}
.product-photo { margin: 0; }
.product-photo img {
  width: 100%;
  display: block;
  border: 1px solid var(--line);
  background: #fff;
}

table {
  width: 100%;
  border-collapse: collapse;
  background: var(--surface);
  font-size: 15px;
}
th, td {
  border-bottom: 1px solid var(--line);
  padding: 14px 16px;
  text-align: left;
  vertical-align: top;
}
th {
  background: linear-gradient(90deg, #0ea5e9, #38bdf8);
  color: #fff;
  font-weight: 600;
}
tr:nth-child(even) td { background: #f3f9ff; }

.faq .qa, article.qa {
  background: var(--surface);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  margin: 0;
  padding: 16px 18px 14px;
}
.faq .qa h3, article.qa h3 { margin: 0 0 8px; font-size: 17px; }
.faq .qa p, article.qa p { margin: 0; color: var(--ink-soft); }
.faq-body p { margin: 0 0 10px; color: var(--ink); }
.faq-body p:last-child { margin-bottom: 0; }
.meta-line { color: var(--ink-soft); font-size: 0.9em; margin: 0 0 8px; }

.note {
  background: #f0f9ff;
  border: 1px solid var(--line);
  padding: 14px 16px;
}
.source { font-size: 13px; color: var(--ink-soft); margin-top: 12px; }

.cta {
  display: inline-block;
  background: linear-gradient(135deg, #0ea5e9, #38bdf8);
  color: #fff !important;
  text-decoration: none;
  padding: 11px 18px;
  margin: 6px 10px 0 0;
  border-radius: 999px;
  box-shadow: 0 8px 18px rgba(14, 165, 233, 0.28);
}
.cta.ghost {
  background: transparent;
  color: var(--ink) !important;
  border: 1px solid var(--ink);
}
.cta:hover { background: var(--accent-hover); }
.cta.ghost:hover {
  border-color: var(--accent);
  color: var(--accent) !important;
  background: transparent;
}

.partners {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 12px;
  padding: 8px 0 28px;
}
.partners span {
  border: 1px solid var(--line);
  background: var(--surface);
  padding: 8px 14px;
  font-size: 13px;
  color: var(--ink-soft);
}

.split-content {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 24px 32px;
  align-items: stretch;
}
.split-content > table {
  height: 100%;
  margin: 0;
}
.split-content .about-side {
  height: 100%;
  box-sizing: border-box;
  background: var(--surface);
  border: 1px solid var(--line);
  padding: 18px 20px 16px;
  display: flex;
  flex-direction: column;
}
.split-content .about-side h2 {
  margin: 0 0 12px;
  font-size: 18px;
}
.split-content .article-body {
  margin: 0;
  max-width: none;
  flex: 1;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink-soft);
}
.split-content .article-body p:last-child { margin-bottom: 0; }

dl.terms {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px 48px;
}
dl.terms dt { font-weight: 700; margin-top: 16px; }
dl.terms dd { margin: 6px 0 0; color: var(--ink-soft); }

.article-body { overflow-wrap: anywhere; max-width: none; }
.article-body h2 { font-size: 22px; margin: 28px 0 12px; }
.article-body h3 { font-size: 18px; margin: 22px 0 10px; }
.article-body p { margin: 0 0 14px; }
.article-body ul, .article-body ol { margin: 0 0 14px; padding-left: 1.4em; }

.site-footer {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 30;
  width: 100%;
  background: linear-gradient(180deg, #ffffff 0%, #e8f6ff 100%);
  color: var(--ink-soft);
  border-top: 1px solid var(--line);
  box-shadow: 0 -6px 20px rgba(14, 165, 233, 0.08);
  margin-top: 0;
  padding: 16px 16px 14px;
  font-size: 13px;
  text-align: center;
}
.foot-inner {
  width: min(720px, 100%);
  margin: 0 auto;
  padding: 0;
}
.foot-brand {
  margin: 0 0 10px;
  color: var(--ink);
  font-weight: 600;
}
.foot-brand span {
  font-weight: 400;
  color: var(--accent-deep);
  margin-left: 10px;
}
.foot-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 6px 16px;
  margin: 0 0 12px;
}
.site-footer a { color: var(--accent-deep); text-decoration: none; }
.site-footer a:hover { color: var(--accent); text-decoration: underline; }
.foot-grid { display: none; }
.friend-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  gap: 8px 14px;
  margin: 0 0 10px;
  padding: 0;
  border: 0;
  font-size: 12px;
  color: var(--ink-soft);
}
.legal {
  border: 0;
  margin: 0;
  padding: 0;
  color: #7a93a6;
  font-size: 12px;
}

@media (max-width: 1100px) {
  :root { --gutter: 5vw; }
  .wrap, .nav-inner { width: calc(100% - 40px); }
  .section-head, .split-content, dl.terms, .stats-row, .faq {
    grid-template-columns: 1fr;
  }
  .section-head { grid-template-columns: 1fr; }
  .product-grid { grid-template-columns: 1fr 1fr; }
  .product-detail { grid-template-columns: 1fr; }
}

@media (max-width: 760px) {
  :root { --gutter: 24px; }
  .wrap, .nav-inner { width: calc(100% - 32px); }
  .nav-inner { flex-wrap: wrap; gap: 12px; }
  .nav-toggle { display: inline-block; }
  .nav { display: none; width: 100%; justify-content: flex-start; }
  .nav.open { display: flex; }
  .brand-zh { font-size: 24px; }
  .grid-3, .grid-2, .cards.grid-3, .faq, .foot-grid, dl.terms, .product-grid {
    grid-template-columns: 1fr;
  }
  .hero h1, .page-hero h1 { font-size: 32px; }
}