:root {
  --bg: #f8fafc;
  --surface: #ffffff;
  --border: #e2e8f0;
  --text: #0f172a;
  --muted: #475569;
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --emerald: #059669;
  --radius: 14px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
}
code {
  background: #f1f5f9;
  border: 1px solid #cbd5e1;
  padding: 1px 6px;
  border-radius: 5px;
  font-family: "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.88em;
  color: #0f172a;
}
.site-nav {
  background: #0f172a;
  color: #f8fafc;
  padding: 12px 20px;
}
.site-nav-inner {
  max-width: 1080px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}
.site-nav a {
  color: #cbd5e1;
  text-decoration: none;
  font-size: 13.5px;
  font-weight: 600;
}
.site-nav a:hover { color: #ffffff; }
.nav-links { display: flex; gap: 14px; flex-wrap: wrap; align-items: center; }
.nav-cta {
  background: #2563eb;
  color: #ffffff !important;
  padding: 6px 12px;
  border-radius: 7px;
}
.wrap {
  max-width: 960px;
  margin: 0 auto;
  padding: 28px 20px 56px;
}
.hero-box {
  background: linear-gradient(135deg, #ffffff 0%, #eff6ff 100%);
  border: 1px solid #bfdbfe;
  border-radius: 18px;
  padding: 28px;
  box-shadow: 0 8px 28px rgba(15, 23, 42, 0.06);
}
.kicker {
  display: inline-block;
  font-size: 12px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: #1d4ed8;
  background: #dbeafe;
  padding: 4px 10px;
  border-radius: 999px;
  margin-bottom: 10px;
}
h1 {
  margin: 0 0 12px 0;
  font-size: clamp(24px, 3.4vw, 34px);
  line-height: 1.22;
  letter-spacing: -0.02em;
}
.lead {
  margin: 0 0 20px 0;
  font-size: 16px;
  color: var(--muted);
}
.cta-row {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}
.cta-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: linear-gradient(135deg, #2563eb, #4f46e5);
  color: #ffffff;
  text-decoration: none;
  font-weight: 800;
  font-size: 15.5px;
  padding: 13px 22px;
  border-radius: 11px;
  box-shadow: 0 6px 20px rgba(37, 99, 235, 0.3);
  transition: transform 0.14s;
}
.cta-btn:hover { transform: translateY(-1px); }
.cta-btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: #ffffff;
  color: #1e293b;
  border: 1px solid #cbd5e1;
  text-decoration: none;
  font-weight: 700;
  font-size: 14px;
  padding: 12px 18px;
  border-radius: 11px;
  transition: border-color 0.14s, background 0.14s;
}
.cta-btn-secondary:hover {
  border-color: #2563eb;
  background: #f8fafc;
}
.cta-sub {
  margin-top: 9px;
  font-size: 12.5px;
  color: #475569;
}
.zh-callout {
  margin-top: 16px;
  padding: 10px 14px;
  background: #f0fdf4;
  border: 1px solid #bbf7d0;
  border-radius: 10px;
  font-size: 13.5px;
  color: #166534;
}
.section-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  margin-top: 20px;
}
.section-card h2 {
  margin: 0 0 14px 0;
  font-size: 20px;
}
.spec-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}
.spec-table th, .spec-table td {
  padding: 10px 12px;
  border-bottom: 1px solid var(--border);
  text-align: left;
  vertical-align: top;
}
.spec-table th {
  background: #f8fafc;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: #334155;
}
.checklist-box {
  background: #f8fafc;
  border: 1px solid #cbd5e1;
  border-left: 4px solid #2563eb;
  border-radius: 10px;
  padding: 16px 20px;
}
.checklist-list, .steps-list, .pitfalls-list {
  margin: 0;
  padding-left: 20px;
}
.checklist-list li, .steps-list li, .pitfalls-list li {
  margin-bottom: 10px;
}
.checklist-list li:last-child, .steps-list li:last-child, .pitfalls-list li:last-child {
  margin-bottom: 0;
}
.faq-item {
  padding: 14px 0;
  border-bottom: 1px solid var(--border);
}
.faq-item:last-child { border-bottom: none; padding-bottom: 0; }
.faq-q {
  margin: 0 0 6px 0;
  font-size: 15.5px;
  font-weight: 700;
}
.faq-a {
  margin: 0;
  font-size: 14.5px;
  color: var(--muted);
}
.bottom-cta-banner {
  margin-top: 24px;
  padding: 24px;
  border-radius: 16px;
  background: #0f172a;
  color: #f8fafc;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 12px;
}
.related-card {
  display: block;
  padding: 13px 15px;
  border: 1px solid var(--border);
  border-radius: 10px;
  text-decoration: none;
  color: var(--text);
  background: #f8fafc;
  transition: border-color 0.14s, background 0.14s;
}
.related-card:hover {
  border-color: #93c5fd;
  background: #eff6ff;
}
.related-card strong {
  display: block;
  font-size: 14px;
  color: var(--primary);
  margin-bottom: 4px;
  line-height: 1.38;
}
.related-card span {
  font-size: 12.5px;
  color: var(--muted);
  display: block;
  line-height: 1.48;
}
.hub-controls {
  margin-top: 18px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.hub-search {
  width: 100%;
  padding: 11px 15px;
  font-size: 14.5px;
  border: 1px solid #93c5fd;
  border-radius: 10px;
  background: #ffffff;
  color: var(--text);
}
.hub-pills {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}
.hub-pill {
  display: inline-block;
  padding: 6px 12px;
  border-radius: 999px;
  background: #ffffff;
  border: 1px solid #cbd5e1;
  color: #1e293b;
  text-decoration: none;
  font-size: 12.5px;
  font-weight: 700;
}
.hub-pill:hover {
  border-color: #2563eb;
  color: #1d4ed8;
  background: #eff6ff;
}
.site-footer {
  margin-top: 32px;
  text-align: center;
  font-size: 13px;
  color: #64748b;
}
.site-footer a { color: #2563eb; text-decoration: none; }