:root {
  --bg: #f0f2f7;
  --surface: #ffffff;
  --header-from: #1a1a2e;
  --header-to: #16213e;
  --accent: #6366f1;
  --accent-hover: #4f46e5;
  --text: #1e293b;
  --text-muted: #64748b;
  --border: #e2e8f0;
  --shadow: 0 2px 8px rgba(0,0,0,.08);
  --shadow-hover: 0 6px 20px rgba(0,0,0,.13);
  --radius: 12px;
  --badge-cn: #059669;
  --badge-cn-bg: #d1fae5;
  --badge-intl: #2563eb;
  --badge-intl-bg: #dbeafe;
  --badge-agg: #7c3aed;
  --badge-agg-bg: #ede9fe;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
               "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  font-size: 14px;
  line-height: 1.6;
}

/* ── Header ── */
header {
  background: linear-gradient(135deg, var(--header-from) 0%, var(--header-to) 100%);
  color: #fff;
  padding: 0 24px;
}
.header-inner {
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 0;
  gap: 16px;
}
.header-brand {
  display: flex;
  align-items: center;
  gap: 14px;
}
.header-icon {
  font-size: 32px;
  line-height: 1;
}
.header-brand h1 {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -.3px;
}
.header-brand p {
  font-size: 13px;
  color: rgba(255,255,255,.65);
  margin-top: 2px;
}
.header-meta {
  text-align: right;
  font-size: 12px;
  color: rgba(255,255,255,.6);
  line-height: 1.8;
}
.header-meta span { display: block; }

/* ── Tabs ── */
.tabs-wrap {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 1px 4px rgba(0,0,0,.05);
}
.tabs-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  gap: 4px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}
.tabs-inner::-webkit-scrollbar { display: none; }

.tab {
  flex-shrink: 0;
  padding: 10px 16px;
  border: none;
  background: none;
  color: var(--text-muted);
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  border-bottom: 2px solid transparent;
  transition: color .15s, border-color .15s;
  white-space: nowrap;
}
.tab:hover { color: var(--accent); }
.tab.active {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* ── Main ── */
main {
  max-width: 1280px;
  margin: 0 auto;
  padding: 28px 24px 40px;
}

.loading-msg {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--text-muted);
  justify-content: center;
  padding: 80px 0;
  font-size: 15px;
}
.spinner {
  width: 20px; height: 20px;
  border: 2px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin .7s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ── Quick Guide ── */
.quick-guide {
  background: var(--surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 20px 24px;
  margin-bottom: 32px;
  overflow-x: auto;
}
.quick-guide h2 {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 14px;
  color: var(--text);
}

/* ── Section ── */
.section-block { margin-bottom: 36px; }
.section-block.hidden { display: none; }
.section-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
}
.section-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--text);
}
.section-badge {
  font-size: 11px;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: 20px;
}
.badge-cn    { color: var(--badge-cn);   background: var(--badge-cn-bg); }
.badge-intl  { color: var(--badge-intl); background: var(--badge-intl-bg); }
.badge-agg   { color: var(--badge-agg);  background: var(--badge-agg-bg); }

.section-intro {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 14px;
  padding-left: 2px;
}
.section-intro blockquote {
  margin: 0;
  padding: 0;
  border: none;
  font-style: normal;
}

.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 16px;
}

/* ── Tool Card ── */
.tool-card {
  background: var(--surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  transition: box-shadow .2s, transform .2s;
  overflow: hidden;
}
.tool-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}
.card-body {
  padding: 18px 20px 14px;
  flex: 1;
}
.card-title {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--text);
}

/* Markdown inside card */
.card-body table {
  width: 100%;
  border-collapse: collapse;
  font-size: 12.5px;
  margin: 8px 0;
}
.card-body th {
  background: #f8fafc;
  font-weight: 600;
  color: var(--text-muted);
  padding: 5px 8px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}
.card-body td {
  padding: 5px 8px;
  border-bottom: 1px solid #f1f5f9;
  color: var(--text);
  vertical-align: top;
}
.card-body tr:last-child td { border-bottom: none; }
.card-body tr:hover td { background: #fafbff; }
.card-body p { font-size: 12.5px; color: var(--text-muted); margin: 4px 0; }
.card-body strong { color: var(--text); }
.card-body ul { padding-left: 16px; margin: 4px 0; }
.card-body li { font-size: 12.5px; color: var(--text-muted); margin: 2px 0; }
.card-body blockquote {
  border-left: 3px solid #fbbf24;
  margin: 8px 0;
  padding: 6px 10px;
  background: #fffbeb;
  border-radius: 4px;
  font-size: 12px;
  color: #92400e;
}

/* ── Card Links ── */
.card-links {
  padding: 10px 20px 14px;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  border-top: 1px solid #f1f5f9;
}
.link-btn {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 500;
  text-decoration: none;
  background: #f1f5f9;
  color: var(--accent);
  border: 1px solid #e2e8f0;
  transition: background .15s, color .15s;
  white-space: nowrap;
}
.link-btn:hover {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}
.link-btn.primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}
.link-btn.primary:hover { background: var(--accent-hover); }

/* ── Tables (global, for quick guide) ── */
table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}
th {
  background: #f8fafc;
  font-weight: 600;
  color: var(--text-muted);
  padding: 8px 12px;
  text-align: left;
  border-bottom: 2px solid var(--border);
}
td {
  padding: 8px 12px;
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}
tr:hover td { background: #fafbff; }

/* ── Footer ── */
footer {
  text-align: center;
  padding: 20px 24px;
  color: var(--text-muted);
  font-size: 12px;
  border-top: 1px solid var(--border);
  background: var(--surface);
  line-height: 2;
}
footer code {
  background: #f1f5f9;
  padding: 1px 5px;
  border-radius: 4px;
  font-family: ui-monospace, monospace;
  font-size: 11px;
}

/* ── Responsive ── */
@media (max-width: 768px) {
  header { padding: 0 16px; }
  .header-inner { flex-direction: column; align-items: flex-start; gap: 8px; }
  .header-meta { text-align: left; }
  main { padding: 20px 16px 32px; }
  .tabs-inner { padding: 0 16px; }
  .tool-grid { grid-template-columns: 1fr; }
}