:root {
  --dh-bg: #f6f8fb;
  --dh-ink: #1a2332;
  --dh-muted: #5c6b7a;
  --dh-line: #d8e0ea;
  --dh-brand: #0b3d6e;
  --dh-accent: #ff6801;
  --dh-card: #ffffff;
  --dh-max: 760px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body.dh-geo {
  margin: 0;
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  color: var(--dh-ink);
  background: var(--dh-bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

body.dh-geo.en {
  font-family: "Source Sans 3", "Segoe UI", "Helvetica Neue", Arial, sans-serif;
}

a { color: var(--dh-brand); text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { color: var(--dh-accent); }

.dh-wrap { max-width: var(--dh-max); margin: 0 auto; padding: 0 20px; }

.dh-top {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--dh-line);
}

.dh-top-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.dh-brand {
  display: flex;
  flex-direction: column;
  gap: 2px;
  color: inherit;
  text-decoration: none;
}

.dh-brand strong {
  font-size: 16px;
  color: var(--dh-brand);
}

.dh-brand span {
  font-size: 12px;
  color: var(--dh-muted);
}

.dh-nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 16px;
  font-size: 14px;
}

.dh-nav a { text-decoration: none; color: var(--dh-ink); }
.dh-nav a:hover { color: var(--dh-accent); }

.dh-lang {
  display: inline-flex;
  border: 1px solid var(--dh-line);
  border-radius: 999px;
  overflow: hidden;
  font-size: 13px;
}

.dh-lang a {
  padding: 4px 10px;
  text-decoration: none;
  color: var(--dh-muted);
  background: #fff;
}

.dh-lang a.is-active {
  background: var(--dh-brand);
  color: #fff;
}

.dh-hero {
  padding: 40px 0 12px;
}

.dh-hero .eyebrow {
  display: inline-block;
  font-size: 12px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--dh-accent);
  font-weight: 600;
  margin-bottom: 10px;
}

.dh-hero h1 {
  margin: 0 0 16px;
  font-size: clamp(26px, 4vw, 36px);
  line-height: 1.25;
  color: var(--dh-brand);
}

.dh-answer {
  background: var(--dh-card);
  border: 1px solid var(--dh-line);
  border-left: 4px solid var(--dh-accent);
  border-radius: 8px;
  padding: 16px 18px;
  margin: 0 0 28px;
  font-size: 16px;
}

.dh-article h2 {
  margin: 32px 0 12px;
  font-size: 22px;
  color: var(--dh-brand);
}

.dh-article h3 {
  margin: 20px 0 8px;
  font-size: 17px;
}

.dh-article p,
.dh-article li {
  color: var(--dh-ink);
  font-size: 15.5px;
}

.dh-article ul {
  padding-left: 1.2em;
  margin: 0 0 16px;
}

.dh-table-wrap {
  overflow-x: auto;
  margin: 12px 0 24px;
  border: 1px solid var(--dh-line);
  border-radius: 8px;
  background: #fff;
}

table.dh-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

table.dh-table th,
table.dh-table td {
  padding: 10px 12px;
  border-bottom: 1px solid var(--dh-line);
  text-align: left;
  vertical-align: top;
}

table.dh-table th {
  background: #eef3f8;
  color: var(--dh-brand);
  font-weight: 600;
  white-space: nowrap;
}

table.dh-table tr:last-child td { border-bottom: 0; }

.dh-faq details {
  background: #fff;
  border: 1px solid var(--dh-line);
  border-radius: 8px;
  padding: 12px 14px;
  margin: 0 0 10px;
}

.dh-faq summary {
  cursor: pointer;
  font-weight: 600;
  color: var(--dh-brand);
}

.dh-faq details p {
  margin: 10px 0 0;
  color: var(--dh-muted);
}

.dh-cta {
  margin: 36px 0;
  padding: 20px;
  border-radius: 10px;
  background: linear-gradient(135deg, #0b3d6e, #145a94);
  color: #fff;
}

.dh-cta h2 {
  margin: 0 0 8px;
  color: #fff;
  font-size: 20px;
}

.dh-cta p { margin: 0 0 14px; color: rgba(255,255,255,0.9); }

.dh-cta-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.dh-cta a {
  display: inline-block;
  padding: 8px 14px;
  border-radius: 6px;
  background: var(--dh-accent);
  color: #fff;
  text-decoration: none;
  font-weight: 600;
}

.dh-cta a.secondary {
  background: transparent;
  border: 1px solid rgba(255,255,255,0.55);
}

.dh-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 14px;
  margin: 20px 0 32px;
}

.dh-card {
  display: block;
  background: #fff;
  border: 1px solid var(--dh-line);
  border-radius: 10px;
  padding: 16px;
  text-decoration: none;
  color: inherit;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.dh-card:hover {
  border-color: var(--dh-accent);
  transform: translateY(-2px);
  color: inherit;
}

.dh-card h3 {
  margin: 0 0 8px;
  font-size: 17px;
  color: var(--dh-brand);
}

.dh-card p {
  margin: 0;
  font-size: 14px;
  color: var(--dh-muted);
}

.dh-footer {
  margin-top: 48px;
  padding: 28px 0 40px;
  border-top: 1px solid var(--dh-line);
  background: #fff;
  font-size: 13px;
  color: var(--dh-muted);
}

.dh-footer .dh-wrap {
  max-width: 1100px;
}

.dh-footer strong { color: var(--dh-ink); }

.dh-footer a { color: var(--dh-brand); }

@media (max-width: 640px) {
  .dh-top-inner { align-items: flex-start; flex-direction: column; }
  .dh-hero { padding-top: 28px; }
}