@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&family=JetBrains+Mono:wght@400;500;600&display=swap');

:root {
  --bg: #0b1220;
  --bg-raised: #0f172a;
  --surface: rgba(51, 65, 85, 0.16);
  --surface-solid: #141d33;
  --surface-hover: rgba(51, 65, 85, 0.3);
  --border: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.16);
  --text: #f8fafc;
  --text-secondary: #94a3b8;
  --text-tertiary: #64748b;
  --accent: #0085ff;
  --accent-2: #38bdf8;
  --accent-glow: rgba(0, 133, 255, 0.35);
  --danger: #f87171;
  --warning: #fbbf24;
  --success: #34d399;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-pill: 50px;
  --font-sans: 'Inter', -apple-system, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, 'SFMono-Regular', Menlo, Consolas, monospace;
  --header-h: 72px;
  --space-1: 4px; --space-2: 8px; --space-3: 12px; --space-4: 16px;
  --space-5: 24px; --space-6: 32px; --space-7: 48px; --space-8: 64px; --space-9: 96px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  background-image:
    radial-gradient(ellipse 900px 500px at 15% -10%, rgba(0, 133, 255, 0.16), transparent 60%),
    radial-gradient(ellipse 700px 500px at 100% 0%, rgba(56, 189, 248, 0.10), transparent 55%);
  background-attachment: fixed;
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  min-height: 100dvh;
}
img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; }
ul { list-style: none; margin: 0; padding: 0; }
h1, h2, h3, h4, p { margin: 0; }
.icon { width: 1.15em; height: 1.15em; flex-shrink: 0; }

::selection { background: var(--accent-glow); color: #fff; }

/* focus visibility */
a:focus-visible, button:focus-visible, input:focus-visible {
  outline: 2px solid var(--accent-2);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ---------- layout shells ---------- */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--space-5);
}
@media (max-width: 640px) {
  .container { padding: 0 var(--space-4); }
}

/* ---------- header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  display: flex;
  align-items: center;
  background: rgba(11, 18, 32, 0.75);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
}
.site-header .container { display: flex; align-items: center; gap: var(--space-6); width: 100%; }
.brand { display: flex; align-items: center; gap: var(--space-2); font-weight: 700; font-size: 1.05rem; letter-spacing: -0.01em; flex-shrink: 0; }
.brand .brand-mark {
  width: 34px; height: 34px; border-radius: 9px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  display: flex; align-items: center; justify-content: center;
  box-shadow: 0 0 0 1px rgba(255,255,255,0.12), 0 4px 16px var(--accent-glow);
}
.brand .brand-mark .icon { color: #fff; width: 18px; height: 18px; }
.brand small { display: block; font-weight: 500; font-size: 0.68rem; color: var(--text-tertiary); letter-spacing: 0.02em; }

.main-nav { display: flex; align-items: center; gap: var(--space-5); flex: 1; }
.main-nav a {
  color: var(--text-secondary); font-size: 0.92rem; font-weight: 500;
  padding: var(--space-2) 0; transition: color 0.15s ease; position: relative;
}
.main-nav a:hover, .main-nav a.active { color: var(--text); }
.main-nav a.active::after {
  content: ''; position: absolute; left: 0; right: 0; bottom: -4px; height: 2px;
  background: linear-gradient(90deg, var(--accent), var(--accent-2)); border-radius: 2px;
}

.header-search {
  display: flex; align-items: center; gap: var(--space-2);
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-pill);
  padding: 8px 16px; width: 280px; transition: border-color 0.15s ease, background 0.15s ease;
}
.header-search:focus-within { border-color: var(--accent); background: var(--surface-hover); }
.header-search .icon { color: var(--text-tertiary); width: 16px; height: 16px; }
.header-search input {
  background: none; border: none; color: var(--text); font-size: 0.88rem; width: 100%; outline: none;
  font-family: inherit;
}
.header-search input::placeholder { color: var(--text-tertiary); }

.header-gh {
  display: flex; align-items: center; gap: 6px; padding: 9px 14px;
  border: 1px solid var(--border); border-radius: var(--radius-pill); font-size: 0.85rem; font-weight: 500;
  color: var(--text-secondary); flex-shrink: 0; transition: all 0.15s ease;
}
.header-gh:hover { color: var(--text); border-color: var(--border-strong); background: var(--surface); }
.header-gh .icon { width: 16px; height: 16px; }

.nav-toggle { display: none; background: none; border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 8px; color: var(--text); }

@media (max-width: 860px) {
  .main-nav-links, .header-search { display: none; }
  .nav-toggle { display: flex; }
  .header-gh span { display: none; }
}

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 13px 26px; border-radius: var(--radius-pill); font-size: 0.92rem; font-weight: 600;
  border: 1px solid transparent; transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease, border-color .15s ease;
  white-space: nowrap;
}
.btn-primary { background: linear-gradient(135deg, var(--accent), #0068cc); color: #fff; box-shadow: 0 8px 24px var(--accent-glow); }
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 10px 30px var(--accent-glow); }
.btn-ghost { background: var(--surface); color: var(--text); border-color: var(--border); }
.btn-ghost:hover { border-color: var(--border-strong); background: var(--surface-hover); }
.btn:active { transform: translateY(0); }
.btn .icon { width: 16px; height: 16px; }
.btn-sm { padding: 8px 16px; font-size: 0.82rem; }

/* ---------- hero ---------- */
.hero { padding: var(--space-9) 0 var(--space-8); text-align: center; }
.hero-badge {
  display: inline-flex; align-items: center; gap: 8px; padding: 7px 16px 7px 8px;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-pill);
  font-size: 0.8rem; color: var(--text-secondary); margin-bottom: var(--space-5);
}
.hero-badge .dot { width: 20px; height: 20px; border-radius: 50%; background: var(--surface-hover); display:flex; align-items:center; justify-content:center; }
.hero-badge .dot .icon { width: 12px; height: 12px; color: var(--success); }
.hero h1 {
  font-size: clamp(2.4rem, 5.2vw, 4rem); font-weight: 800; letter-spacing: -0.03em; line-height: 1.06;
  max-width: 900px; margin: 0 auto var(--space-5);
}
.hero h1 .grad {
  background: linear-gradient(135deg, var(--accent-2), var(--accent) 60%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero p.lead {
  max-width: 620px; margin: 0 auto var(--space-7); color: var(--text-secondary); font-size: 1.08rem; line-height: 1.6;
}
.hero-actions { display: flex; align-items: center; justify-content: center; gap: var(--space-3); flex-wrap: wrap; margin-bottom: var(--space-8); }

.hero-search {
  max-width: 640px; margin: 0 auto var(--space-8); display: flex; align-items: center; gap: 10px;
  background: var(--surface-solid); border: 1px solid var(--border); border-radius: var(--radius-pill);
  padding: 8px 8px 8px 22px; box-shadow: 0 20px 60px -20px rgba(0,0,0,0.6);
}
.hero-search:focus-within { border-color: var(--accent); }
.hero-search .icon { color: var(--text-tertiary); width: 20px; height: 20px; }
.hero-search input { flex: 1; background: none; border: none; outline: none; color: var(--text); font-size: 1rem; font-family: inherit; }
.hero-search input::placeholder { color: var(--text-tertiary); }
.hero-search button { border-radius: var(--radius-pill); }

.stat-row { display: flex; align-items: center; justify-content: center; gap: var(--space-8); flex-wrap: wrap; }
.stat { text-align: center; }
.stat .num { font-size: 2rem; font-weight: 800; letter-spacing: -0.02em; background: linear-gradient(135deg,#fff,#a9c7ff); -webkit-background-clip: text; background-clip: text; color: transparent; }
.stat .lbl { font-size: 0.82rem; color: var(--text-tertiary); margin-top: 2px; }
.stat-sep { width: 1px; height: 34px; background: var(--border); }
@media (max-width: 640px) { .stat-row { gap: var(--space-5); } .stat-sep { display: none; } }

/* ---------- section headers ---------- */
.section { padding: var(--space-8) 0; }
.section-head { display: flex; align-items: flex-end; justify-content: space-between; gap: var(--space-4); margin-bottom: var(--space-6); flex-wrap: wrap; }
.section-head h2 { font-size: 1.7rem; font-weight: 700; letter-spacing: -0.02em; }
.section-head p { color: var(--text-secondary); margin-top: 6px; max-width: 520px; }
.eyebrow { display: block; font-size: 0.78rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.08em; color: var(--accent-2); margin-bottom: 10px; }

/* ---------- category grid ---------- */
.cat-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-4); }
@media (max-width: 980px) { .cat-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 620px) { .cat-grid { grid-template-columns: 1fr; } }

.card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg);
  padding: var(--space-5); transition: transform 0.18s ease, border-color 0.18s ease, background 0.18s ease, box-shadow .18s ease;
}
a.card { display: block; }
a.card:hover, .card.interactive:hover {
  transform: translateY(-3px); border-color: rgba(0,133,255,0.4); background: var(--surface-hover);
  box-shadow: 0 16px 40px -16px rgba(0,133,255,0.25);
}

.cat-card { display: flex; flex-direction: column; gap: var(--space-4); position: relative; overflow: hidden; }
.cat-card .cat-icon {
  width: 46px; height: 46px; border-radius: 12px; background: linear-gradient(135deg, rgba(0,133,255,0.25), rgba(56,189,248,0.12));
  border: 1px solid rgba(0,133,255,0.3); display: flex; align-items: center; justify-content: center; color: var(--accent-2);
}
.cat-card .cat-icon .icon { width: 22px; height: 22px; }
.cat-card h3 { font-size: 1.08rem; font-weight: 700; letter-spacing: -0.01em; }
.cat-card p { color: var(--text-secondary); font-size: 0.88rem; line-height: 1.55; flex: 1; }
.cat-card .cat-meta { display: flex; align-items: center; justify-content: space-between; font-size: 0.8rem; color: var(--text-tertiary); padding-top: var(--space-3); border-top: 1px solid var(--border); }
.cat-card .cat-meta .count { color: var(--accent-2); font-weight: 700; font-family: var(--font-mono); }
.cat-card.is-deprecated .cat-icon { background: linear-gradient(135deg, rgba(251,191,36,0.22), rgba(251,191,36,0.08)); border-color: rgba(251,191,36,0.3); color: var(--warning); }
.cat-card.is-empty { opacity: 0.55; }

/* pill badges */
.badge {
  display: inline-flex; align-items: center; gap: 5px; padding: 3px 10px; border-radius: var(--radius-pill);
  font-size: 0.72rem; font-weight: 600; background: var(--surface); border: 1px solid var(--border); color: var(--text-secondary);
  font-family: var(--font-mono); letter-spacing: 0.01em;
}
.badge-accent { background: rgba(0,133,255,0.14); border-color: rgba(0,133,255,0.35); color: var(--accent-2); }
.badge-warning { background: rgba(251,191,36,0.14); border-color: rgba(251,191,36,0.35); color: var(--warning); }
.badge-tag { background: rgba(148,163,184,0.1); }

/* ---------- breadcrumb ---------- */
.breadcrumb { display: flex; align-items: center; gap: 8px; font-size: 0.85rem; color: var(--text-tertiary); flex-wrap: wrap; padding: var(--space-5) 0 var(--space-3); }
.breadcrumb a:hover { color: var(--text); }
.breadcrumb .sep { color: var(--text-tertiary); opacity: 0.5; }
.breadcrumb .current { color: var(--text-secondary); }

/* ---------- page header (category/subcat/rule) ---------- */
.page-head { padding: var(--space-4) 0 var(--space-7); border-bottom: 1px solid var(--border); margin-bottom: var(--space-6); }
.page-head-top { display: flex; align-items: flex-start; gap: var(--space-4); }
.page-icon {
  width: 56px; height: 56px; border-radius: 14px; flex-shrink: 0;
  background: linear-gradient(135deg, rgba(0,133,255,0.22), rgba(56,189,248,0.08)); border: 1px solid rgba(0,133,255,0.3);
  display: flex; align-items: center; justify-content: center; color: var(--accent-2);
}
.page-icon .icon { width: 26px; height: 26px; }
.page-head h1 { font-size: 2rem; font-weight: 800; letter-spacing: -0.02em; margin-bottom: 6px; }
.page-head .desc { color: var(--text-secondary); max-width: 640px; line-height: 1.6; }
.page-head-meta { display: flex; gap: var(--space-3); margin-top: var(--space-4); flex-wrap: wrap; }

/* ---------- subcategory chips ---------- */
.subcat-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: var(--space-3); margin-bottom: var(--space-7); }
.subcat-card { display: flex; align-items: center; justify-content: space-between; padding: var(--space-4); }
.subcat-card .name { font-weight: 600; font-size: 0.95rem; }
.subcat-card .count { font-family: var(--font-mono); color: var(--accent-2); font-weight: 700; font-size: 0.85rem; }

/* ---------- toolbar (filter/sort) ---------- */
.toolbar { display: flex; align-items: center; gap: var(--space-3); margin-bottom: var(--space-5); flex-wrap: wrap; }
.toolbar .filter-input {
  flex: 1; min-width: 220px; display: flex; align-items: center; gap: 8px;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-pill); padding: 10px 16px;
}
.toolbar .filter-input .icon { width: 16px; height: 16px; color: var(--text-tertiary); }
.toolbar .filter-input input { flex: 1; background: none; border: none; outline: none; color: var(--text); font-family: inherit; font-size: 0.9rem; }
.toolbar .filter-input input::placeholder { color: var(--text-tertiary); }
.toolbar select {
  background: var(--surface); border: 1px solid var(--border); color: var(--text); border-radius: var(--radius-pill);
  padding: 10px 16px; font-size: 0.85rem; font-family: inherit; outline: none;
}
.toolbar .result-count { font-size: 0.82rem; color: var(--text-tertiary); white-space: nowrap; }

/* ---------- rule list ---------- */
.rule-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: var(--space-3); }
@media (max-width: 780px) { .rule-list { grid-template-columns: 1fr; } }

.rule-card { padding: var(--space-4) var(--space-5); }
.rule-card .rule-card-top { display: flex; align-items: start; justify-content: space-between; gap: var(--space-3); margin-bottom: 8px; }
.rule-card h4 { font-family: var(--font-mono); font-size: 0.92rem; font-weight: 600; color: var(--text); word-break: break-word; }
.rule-card .file-tag { font-size: 0.74rem; color: var(--text-tertiary); font-family: var(--font-mono); margin-bottom: 8px; display: flex; align-items: center; gap: 5px; }
.rule-card p.snippet { font-size: 0.82rem; color: var(--text-secondary); line-height: 1.5; margin-bottom: 10px; min-height: 1.2em; }
.rule-card .tags-row { display: flex; gap: 6px; flex-wrap: wrap; }

.load-more-wrap { display: flex; justify-content: center; margin-top: var(--space-7); }

.empty-state { text-align: center; padding: var(--space-9) var(--space-4); color: var(--text-tertiary); }
.empty-state .icon { width: 40px; height: 40px; margin: 0 auto var(--space-4); color: var(--text-tertiary); }
.empty-state h3 { color: var(--text-secondary); font-size: 1.1rem; margin-bottom: 6px; }

/* ---------- rule detail ---------- */
.rule-detail-grid { display: grid; grid-template-columns: 1fr 300px; gap: var(--space-6); align-items: start; }
@media (max-width: 940px) { .rule-detail-grid { grid-template-columns: 1fr; } }

.code-panel { background: #070c17; border: 1px solid var(--border); border-radius: var(--radius-lg); overflow: hidden; }
.code-panel-head { display: flex; align-items: center; justify-content: space-between; padding: var(--space-3) var(--space-4); border-bottom: 1px solid var(--border); background: rgba(255,255,255,0.02); }
.code-panel-head .dots { display: flex; gap: 6px; }
.code-panel-head .dots span { width: 10px; height: 10px; border-radius: 50%; background: var(--border-strong); }
.code-panel-head .fname { font-family: var(--font-mono); font-size: 0.78rem; color: var(--text-tertiary); }
.code-panel pre {
  margin: 0; padding: var(--space-5); overflow-x: auto; font-family: var(--font-mono); font-size: 0.86rem; line-height: 1.65;
}
.code-panel code { white-space: pre; }

.tok-comment { color: #64748b; font-style: italic; }
.tok-string { color: #a5d6a7; }
.tok-var { color: #fbbf24; }
.tok-decl { color: #38bdf8; font-weight: 600; }
.tok-section { color: #0085ff; font-weight: 700; }
.tok-kw { color: #c792ea; }
.tok-mod { color: #f78c6c; }
.tok-builtin { color: #82aaff; }
.tok-num { color: #f07178; }

.side-panel { display: flex; flex-direction: column; gap: var(--space-4); }
.info-card h4 { font-size: 0.78rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--text-tertiary); margin-bottom: var(--space-3); font-weight: 700; }
.meta-list { display: flex; flex-direction: column; gap: 10px; }
.meta-row { display: flex; flex-direction: column; gap: 3px; }
.meta-row .k { font-size: 0.72rem; color: var(--text-tertiary); text-transform: uppercase; letter-spacing: 0.04em; }
.meta-row .v { font-size: 0.86rem; color: var(--text); word-break: break-word; line-height: 1.45; }
.meta-row .v a { color: var(--accent-2); }
.chip-row { display: flex; gap: 6px; flex-wrap: wrap; }

.related-list { display: flex; flex-direction: column; gap: 2px; }
.related-list a { display: flex; align-items: center; justify-content: space-between; padding: 9px 4px; font-size: 0.84rem; font-family: var(--font-mono); color: var(--text-secondary); border-radius: 8px; }
.related-list a:hover { color: var(--text); background: var(--surface); }

/* ---------- about section ---------- */
.about-grid { display: grid; grid-template-columns: 1.1fr 1fr; gap: var(--space-8); align-items: center; }
@media (max-width: 860px) { .about-grid { grid-template-columns: 1fr; gap: var(--space-6); } }
.about-copy p { color: var(--text-secondary); line-height: 1.7; margin-bottom: var(--space-4); }
.feature-list { display: flex; flex-direction: column; gap: var(--space-3); margin-top: var(--space-5); }
.feature-item { display: flex; gap: var(--space-3); align-items: flex-start; }
.feature-item .fi-icon { width: 30px; height: 30px; border-radius: 8px; background: var(--surface); border: 1px solid var(--border); display: flex; align-items: center; justify-content: center; color: var(--accent-2); flex-shrink: 0; }
.feature-item .fi-icon .icon { width: 15px; height: 15px; }
.feature-item strong { font-size: 0.92rem; display: block; margin-bottom: 2px; }
.feature-item span { font-size: 0.84rem; color: var(--text-secondary); }

.snippet-preview { background: var(--surface-solid); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: var(--space-5); box-shadow: 0 24px 60px -24px rgba(0,133,255,0.25); }
.snippet-preview pre { margin: 0; font-family: var(--font-mono); font-size: 0.8rem; line-height: 1.6; overflow-x: auto; }

/* ---------- CTA band ---------- */
.cta-band {
  margin: var(--space-8) 0; padding: var(--space-8) var(--space-6); border-radius: 24px; text-align: center;
  background: linear-gradient(135deg, rgba(0,133,255,0.18), rgba(56,189,248,0.06));
  border: 1px solid rgba(0,133,255,0.25); position: relative; overflow: hidden;
}
.cta-band h2 { font-size: 1.9rem; font-weight: 800; letter-spacing: -0.02em; margin-bottom: var(--space-3); }
.cta-band p { color: var(--text-secondary); max-width: 480px; margin: 0 auto var(--space-6); }

/* ---------- footer ---------- */
.site-footer { border-top: 1px solid var(--border); padding: var(--space-7) 0 var(--space-6); margin-top: var(--space-8); }
.footer-grid { display: flex; justify-content: space-between; align-items: center; gap: var(--space-5); flex-wrap: wrap; }
.footer-links { display: flex; gap: var(--space-5); }
.footer-links a { color: var(--text-tertiary); font-size: 0.85rem; }
.footer-links a:hover { color: var(--text-secondary); }
.footer-note { font-size: 0.8rem; color: var(--text-tertiary); }

/* ---------- loading / skeletons ---------- */
.skel { background: linear-gradient(90deg, var(--surface) 25%, var(--surface-hover) 50%, var(--surface) 75%); background-size: 200% 100%; animation: shimmer 1.4s ease infinite; border-radius: var(--radius-md); }
@keyframes shimmer { 0% { background-position: 200% 0; } 100% { background-position: -200% 0; } }
.skel-card { height: 168px; }
.skel-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: var(--space-3); }
@media (max-width: 780px) { .skel-grid { grid-template-columns: 1fr; } }

.spin { animation: spin 1s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

@media (prefers-reduced-motion: reduce) {
  * { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; scroll-behavior: auto !important; }
}

/* mobile nav drawer */
.mobile-drawer {
  position: fixed; inset: 0; z-index: 200; background: rgba(0,0,0,0.6); backdrop-filter: blur(4px);
  display: none;
}
.mobile-drawer.open { display: block; }
.mobile-drawer .panel {
  position: absolute; top: 0; right: 0; bottom: 0; width: min(300px, 84vw); background: var(--bg-raised);
  border-left: 1px solid var(--border); padding: var(--space-6) var(--space-5); display: flex; flex-direction: column; gap: var(--space-5);
}
.mobile-drawer nav { display: flex; flex-direction: column; gap: var(--space-4); }
.mobile-drawer nav a { font-size: 1rem; font-weight: 600; }
.mobile-drawer .close-btn { align-self: flex-end; background: var(--surface); border: 1px solid var(--border); border-radius: 50%; width: 36px; height: 36px; display: flex; align-items: center; justify-content: center; color: var(--text); }