:root {
  --page: #f7f7f8;
  --surface: #ffffff;
  --surface-soft: #f7f7f8;
  --surface-blue: #f1f2f4;
  --text: #111827;
  --muted: #5f6b7a;
  --subtle: #8a94a3;
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-soft: #eaf1ff;
  --accent: #475569;
  --accent-soft: #eef0f3;
  --border: #e5e7eb;
  --shadow: 0 14px 36px rgba(17, 24, 39, 0.06);
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

.nav-link {
  align-items: center;
  border-radius: 999px;
  border: 1px solid transparent;
  color: var(--muted);
  display: inline-flex;
  font-size: 0.875rem;
  font-weight: 600;
  min-height: 2.5rem;
  padding: 0 1rem;
  transition: color 180ms ease, background 180ms ease, border-color 180ms ease;
}

.nav-link:hover,
.nav-link.is-active {
  background: var(--primary-soft);
  border-color: rgba(37, 99, 235, 0.14);
  color: var(--primary);
}

.mobile-link {
  border-radius: 1rem;
  border: 1px solid transparent;
  color: var(--muted);
  display: block;
  font-size: 0.95rem;
  font-weight: 600;
  padding: 0.75rem 0.9rem;
}

.mobile-link + .mobile-link {
  margin-top: 0.35rem;
}

.mobile-link.is-active {
  background: var(--primary-soft);
  border-color: rgba(37, 99, 235, 0.14);
  color: var(--primary);
}

.section-kicker {
  color: var(--primary);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.section-title {
  color: var(--text);
  font-size: clamp(1.9rem, 3vw, 2.7rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin-top: 0.55rem;
}

.soft-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 1.5rem;
  padding: 1.5rem;
  transition: transform 180ms ease, box-shadow 180ms ease, border-color 180ms ease;
}

.soft-card:hover {
  border-color: rgba(37, 99, 235, 0.25);
  box-shadow: var(--shadow);
  transform: translateY(-3px);
}

.pager-link {
  align-items: center;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--muted);
  display: inline-flex;
  font-size: 0.875rem;
  font-weight: 600;
  min-height: 2.5rem;
  padding: 0 1rem;
}

.pager-link.is-active {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
}

.prose-content {
  color: var(--text);
  line-height: 1.9;
}

.prose-content h2 {
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1.35;
  margin: 1.6rem 0 0.8rem;
}

.prose-content h2:first-child {
  margin-top: 0;
}

.prose-content p {
  color: var(--muted);
  margin: 0.75rem 0;
}

.prose-content code {
  background: var(--surface-blue);
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  color: var(--primary);
  padding: 0.1rem 0.35rem;
}

.whois-table {
  border: 1px solid var(--border);
  border-radius: 1rem;
  overflow: hidden;
}

.whois-row {
  display: grid;
  gap: 0.75rem;
  grid-template-columns: minmax(120px, 0.36fr) 1fr;
  padding: 0.85rem 1rem;
}

.whois-row + .whois-row {
  border-top: 1px solid var(--border);
}

.whois-key {
  color: var(--muted);
  font-size: 0.82rem;
}

.whois-value {
  color: var(--text);
  font-size: 0.9rem;
  overflow-wrap: anywhere;
}

.status-ok {
  background: #f0fdf4;
  border-color: #bbf7d0;
  color: #166534;
}

.status-error {
  background: #fff1f2;
  border-color: #fecdd3;
  color: #be123c;
}

.status-loading {
  background: var(--primary-soft);
  border-color: #bfdbfe;
  color: var(--primary);
}

.hero-kicker {
  color: var(--subtle);
  letter-spacing: 0.08em;
}

.hero-badge {
  background: #ffffff;
  border: 1px solid var(--border);
  box-shadow: none;
}

.hero-badge:hover {
  border-color: rgba(37, 99, 235, 0.28);
}

.section-panel {
  background: #ffffff;
}

.section-panel-soft {
  background: #f7f7f8;
}

.section-panel-muted {
  background: #f7f7f8;
}

.faq-summary {
  align-items: flex-start;
  color: var(--text);
  cursor: pointer;
  display: flex;
  gap: 1rem;
  justify-content: space-between;
  list-style: none;
}

.faq-summary::-webkit-details-marker {
  display: none;
}

.faq-title {
  display: flex;
  gap: 0.75rem;
  line-height: 1.55;
}

.faq-num {
  align-items: center;
  background: var(--page);
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--primary);
  display: inline-flex;
  flex: 0 0 auto;
  font-size: 0.75rem;
  font-weight: 700;
  height: 1.75rem;
  justify-content: center;
  width: 1.75rem;
}

.faq-toggle {
  align-items: center;
  background: var(--primary-soft);
  border-radius: 999px;
  color: var(--primary);
  display: inline-flex;
  flex: 0 0 auto;
  font-size: 0.75rem;
  font-weight: 700;
  height: 1.5rem;
  justify-content: center;
  margin-top: 0.2rem;
  width: 1.5rem;
}

.faq-body {
  color: var(--muted);
  display: grid;
  gap: 0.75rem;
  margin-top: 1rem;
}

.faq-body p {
  line-height: 1.9;
  margin: 0;
}

.faq-list,
.faq-steps {
  color: var(--muted);
  display: grid;
  gap: 0.55rem;
  line-height: 1.75;
  margin: 0;
  padding-left: 1.15rem;
}

.faq-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
}

.faq-tags code {
  background: var(--page);
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--text);
  font-size: 0.8rem;
  padding: 0.22rem 0.55rem;
}

.faq-grid {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.faq-grid h3 {
  color: var(--text);
  font-size: 0.95rem;
  font-weight: 700;
  margin: 0 0 0.55rem;
}

.faq-steps {
  padding-left: 1.15rem;
}

@media (max-width: 640px) {
  .faq-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .whois-row {
    grid-template-columns: 1fr;
  }
}