/* VSAG landing page — brand-aligned (gold gradient + warm graphite) */
:root {
  /* Brand: derived from docs/banner.svg gradients */
  --gold-50:  #fff6dc;
  --gold-100: #fce897;
  --gold-300: #f6d36b;
  --gold-500: #f4bd37;
  --gold-600: #d9a221;
  --gold-700: #a9791a;

  /* Neutrals */
  --ink-950: #0f0d0c;
  --ink-900: #171412;
  --ink-800: #1f1b18;
  --ink-700: #2a2522;
  --ink-600: #3e3a39;
  --ink-400: #7a7370;
  --ink-300: #a8a19d;
  --ink-200: #d8d3cf;
  --ink-100: #efebe7;
  --ink-50:  #f8f5f1;
  --bg:       #ffffff;

  /* Semantic */
  --fg:          var(--ink-900);
  --fg-muted:    var(--ink-400);
  --fg-subtle:   var(--ink-600);
  --surface:     var(--bg);
  --surface-alt: var(--ink-50);
  --border:      rgba(15, 13, 12, 0.08);
  --border-strong: rgba(15, 13, 12, 0.14);
  --accent:      var(--gold-600);
  --accent-hi:   var(--gold-500);

  --radius-sm: 8px;
  --radius:    14px;
  --radius-lg: 22px;

  --shadow-sm: 0 1px 2px rgba(15, 13, 12, 0.04), 0 1px 1px rgba(15, 13, 12, 0.03);
  --shadow:    0 8px 28px rgba(15, 13, 12, 0.08), 0 2px 4px rgba(15, 13, 12, 0.04);
  --shadow-lg: 0 24px 60px rgba(15, 13, 12, 0.14), 0 4px 12px rgba(15, 13, 12, 0.06);

  --mono: ui-monospace, SFMono-Regular, "JetBrains Mono", Menlo, Consolas, monospace;
  --sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue",
          Arial, "Noto Sans", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --fg:          #f4efe7;
    --fg-muted:    #b7ada0;
    --fg-subtle:   #d6ccbe;
    --surface:     #12100e;
    --surface-alt: #1a1714;
    --bg:          #12100e;
    --border:      rgba(255, 244, 220, 0.08);
    --border-strong: rgba(255, 244, 220, 0.16);
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow:    0 8px 28px rgba(0, 0, 0, 0.45);
    --shadow-lg: 0 28px 80px rgba(0, 0, 0, 0.6);
  }
}

/* Reset + base */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--fg);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img, svg { display: block; max-width: 100%; }
a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--gold-700); text-decoration: underline; text-underline-offset: 3px; }
@media (prefers-color-scheme: dark) {
  a:hover { color: var(--gold-300); }
}
code {
  font-family: var(--mono);
  font-size: 0.92em;
  padding: 0.1em 0.35em;
  background: var(--surface-alt);
  border: 1px solid var(--border);
  border-radius: 6px;
}
h1, h2, h3, h4 {
  font-weight: 650;
  letter-spacing: -0.01em;
  color: var(--fg);
  margin: 0 0 0.5em;
}
h1 { font-size: clamp(2.2rem, 4.6vw, 3.4rem); line-height: 1.08; letter-spacing: -0.025em; }
h2 { font-size: clamp(1.6rem, 2.6vw, 2.2rem); line-height: 1.18; letter-spacing: -0.015em; }
h3 { font-size: 1.1rem; }
p  { margin: 0 0 1em; color: var(--fg-subtle); }

.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0;
}
.skip {
  position: absolute; left: -9999px; top: 0;
  background: var(--accent); color: var(--ink-900);
  padding: 0.6em 1em; border-radius: 0 0 var(--radius-sm) 0; font-weight: 600;
}
.skip:focus { left: 0; z-index: 100; }

.container { width: 100%; max-width: 1120px; margin: 0 auto; padding: 0 24px; }

/* Nav */
.nav {
  position: sticky; top: 0; z-index: 40;
  background: color-mix(in oklab, var(--bg) 88%, transparent);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px;
}
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--fg); font-weight: 700; }
.brand:hover { text-decoration: none; }
.brand-mark { filter: drop-shadow(0 1px 2px rgba(244, 189, 55, 0.35)); }
.brand-name {
  font-family: var(--sans); font-weight: 750; font-size: 1.05rem; letter-spacing: 0.02em;
}
.nav-links { display: flex; align-items: center; gap: 22px; }
.nav-links a { color: var(--fg-subtle); font-weight: 500; font-size: 0.95rem; }
.nav-links a:hover { color: var(--fg); text-decoration: none; }
.nav-links .gh {
  display: inline-flex; align-items: center; justify-content: center;
  width: 34px; height: 34px; border-radius: 10px; color: var(--fg-subtle);
  border: 1px solid var(--border); background: var(--surface-alt);
}
.nav-links .gh:hover { color: var(--fg); border-color: var(--border-strong); }
.nav-links .lang {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 34px; height: 34px; padding: 0 10px; border-radius: 10px;
  color: var(--fg-subtle); border: 1px solid var(--border);
  background: var(--surface-alt); font-weight: 600;
}
.nav-links .lang:hover { color: var(--fg); border-color: var(--border-strong); }
@media (max-width: 720px) {
  .nav-links a:not(.gh):not(.lang) { display: none; }
}

/* Hero */
.hero { position: relative; overflow: hidden; padding: clamp(56px, 10vw, 120px) 0 64px; }
.hero-inner { position: relative; z-index: 1; max-width: 820px; }
.eyebrow {
  display: inline-block; margin: 0 0 18px; padding: 5px 12px;
  font-size: 0.78rem; font-weight: 600; letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--gold-700);
  background: linear-gradient(135deg, rgba(252, 232, 151, 0.35), rgba(244, 189, 55, 0.18));
  border: 1px solid rgba(244, 189, 55, 0.4);
  border-radius: 999px;
}
@media (prefers-color-scheme: dark) {
  .eyebrow {
    color: var(--gold-300);
    background: linear-gradient(135deg, rgba(244, 189, 55, 0.18), rgba(244, 189, 55, 0.06));
    border-color: rgba(244, 189, 55, 0.3);
  }
}
.eyebrow.center { display: block; text-align: center; margin-left: auto; margin-right: auto; width: fit-content; }
.grad {
  background: linear-gradient(100deg, var(--gold-500) 0%, var(--gold-300) 45%, var(--gold-700) 100%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.lede {
  font-size: clamp(1.02rem, 1.4vw, 1.18rem);
  color: var(--fg-subtle); max-width: 720px; margin-top: 10px;
}
.lede.left { margin-left: 0; }
.cta-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 28px; }
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 20px; border-radius: 999px; font-weight: 600; font-size: 0.96rem;
  border: 1px solid transparent; transition: transform 0.15s ease, box-shadow 0.2s ease, background 0.2s ease, color 0.2s ease;
  cursor: pointer; white-space: nowrap;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn-primary {
  color: var(--ink-950);
  background: linear-gradient(135deg, var(--gold-100) 0%, var(--gold-500) 100%);
  box-shadow: 0 8px 24px rgba(244, 189, 55, 0.35), inset 0 1px 0 rgba(255, 255, 255, 0.4);
}
.btn-primary:hover {
  box-shadow: 0 12px 32px rgba(244, 189, 55, 0.45), inset 0 1px 0 rgba(255, 255, 255, 0.5);
}
.btn-ghost {
  color: var(--fg);
  background: var(--surface);
  border-color: var(--border-strong);
}
.btn-ghost:hover { background: var(--surface-alt); color: var(--fg); }

.stats {
  display: grid; grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 24px; margin: 44px 0 0; padding: 20px 0 0;
  border-top: 1px dashed var(--border-strong);
}
.stats div { display: flex; flex-direction: column; gap: 2px; }
.stats dt { font-size: 0.8rem; color: var(--fg-muted); letter-spacing: 0.03em; }
.stats dd { margin: 0; font-weight: 650; color: var(--fg); font-size: 1rem; }
@media (max-width: 640px) {
  .stats { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
}

.hero-glow {
  position: absolute; inset: -20% -10% auto auto; width: 70%; height: 520px; pointer-events: none;
  background:
    radial-gradient(ellipse at 70% 30%, rgba(252, 232, 151, 0.55), transparent 55%),
    radial-gradient(ellipse at 30% 70%, rgba(244, 189, 55, 0.35), transparent 60%);
  filter: blur(40px); opacity: 0.9;
}
@media (prefers-color-scheme: dark) {
  .hero-glow {
    background:
      radial-gradient(ellipse at 70% 30%, rgba(244, 189, 55, 0.25), transparent 55%),
      radial-gradient(ellipse at 30% 70%, rgba(244, 189, 55, 0.12), transparent 60%);
  }
}

/* Sections */
.section { padding: clamp(56px, 8vw, 96px) 0; }
.section-alt { background: var(--surface-alt); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.section-title { text-align: center; margin: 6px auto 40px; max-width: 760px; }
.section-title.left { text-align: left; margin-left: 0; }

/* Grids / Cards */
.grid-3 {
  display: grid; gap: 18px;
  grid-template-columns: repeat(3, minmax(0, 1fr));
}
@media (max-width: 900px) { .grid-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 600px) { .grid-3 { grid-template-columns: 1fr; } }

.card {
  padding: 24px; background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}
.card:hover {
  transform: translateY(-2px); box-shadow: var(--shadow);
  border-color: rgba(244, 189, 55, 0.35);
}
.card h3 { margin-top: 14px; }
.card p { margin-bottom: 0; font-size: 0.96rem; }
.card .icon {
  display: inline-flex; align-items: center; justify-content: center;
  width: 40px; height: 40px; border-radius: 12px;
  background: linear-gradient(135deg, rgba(252, 232, 151, 0.5), rgba(244, 189, 55, 0.15));
  color: var(--gold-700); border: 1px solid rgba(244, 189, 55, 0.35);
}
@media (prefers-color-scheme: dark) {
  .card .icon {
    background: linear-gradient(135deg, rgba(244, 189, 55, 0.2), rgba(244, 189, 55, 0.05));
    color: var(--gold-300);
    border-color: rgba(244, 189, 55, 0.28);
  }
}

/* Quickstart code panels */
.qs-grid {
  display: grid; gap: 20px;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}
@media (max-width: 860px) { .qs-grid { grid-template-columns: 1fr; } }
.qs-panel {
  background: var(--ink-950); color: #e9e4da;
  border: 1px solid var(--border-strong); border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow);
}
.qs-panel h3 {
  margin: 0; padding: 14px 18px;
  background: linear-gradient(135deg, rgba(244, 189, 55, 0.18), rgba(244, 189, 55, 0.04));
  border-bottom: 1px solid rgba(255, 244, 220, 0.08);
  color: var(--gold-100); font-size: 0.92rem; letter-spacing: 0.04em; text-transform: uppercase;
}
.qs-panel pre {
  margin: 0; padding: 18px; overflow-x: auto;
  font-family: var(--mono); font-size: 0.88rem; line-height: 1.65; color: #e9e4da;
  background: transparent;
}
.qs-panel pre + pre { border-top: 1px dashed rgba(255, 244, 220, 0.08); }
.qs-panel .code-block + .code-block { border-top: 1px dashed rgba(255, 244, 220, 0.08); }
.qs-panel .code-block { position: relative; }
.qs-panel .code-block pre { padding-right: 76px; }
.copy-btn {
  position: absolute; top: 10px; right: 10px;
  font-family: var(--sans); font-size: 0.74rem; font-weight: 600;
  letter-spacing: 0.06em; text-transform: uppercase;
  color: #e9e4da;
  background: rgba(255, 244, 220, 0.08);
  border: 1px solid rgba(255, 244, 220, 0.18);
  border-radius: 8px;
  padding: 5px 10px;
  cursor: pointer;
  opacity: 0.7;
  transition: opacity 0.15s ease, background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}
.qs-panel .code-block:hover .copy-btn,
.copy-btn:focus-visible { opacity: 1; }
.copy-btn:hover {
  background: rgba(244, 189, 55, 0.18);
  border-color: rgba(244, 189, 55, 0.4);
  color: var(--gold-100);
}
.copy-btn.copied {
  background: rgba(244, 189, 55, 0.28);
  border-color: rgba(244, 189, 55, 0.55);
  color: var(--gold-100);
  opacity: 1;
}
.copy-btn.failed {
  background: rgba(220, 80, 80, 0.22);
  border-color: rgba(220, 80, 80, 0.5);
  color: #ffd6d0;
  opacity: 1;
}
.qs-panel code { background: transparent; border: 0; padding: 0; color: inherit; font-size: inherit; }
.qs-panel .k  { color: #f4bd37; }
.qs-panel .s  { color: #fce897; }
.qs-panel .c  { color: #9a8f7a; font-style: italic; }
.qs-panel .n  { color: #e9c46a; }
.qs-panel .pp { color: #d18a5e; }
.qs-foot { text-align: center; margin-top: 26px; color: var(--fg-muted); font-size: 0.96rem; }

/* Table */
.table-wrap {
  overflow-x: auto; border: 1px solid var(--border); border-radius: var(--radius);
  background: var(--surface); box-shadow: var(--shadow-sm);
}
.matrix { width: 100%; border-collapse: collapse; min-width: 640px; }
.matrix th, .matrix td {
  padding: 14px 18px; text-align: left; border-bottom: 1px solid var(--border);
  font-size: 0.96rem;
}
.matrix thead th {
  font-size: 0.8rem; letter-spacing: 0.06em; text-transform: uppercase;
  color: var(--fg-muted); background: var(--surface-alt);
}
.matrix tbody tr:last-child th, .matrix tbody tr:last-child td { border-bottom: 0; }
.matrix tbody tr.deprecated th,
.matrix tbody tr.deprecated td { color: var(--fg-muted); }
.matrix tbody tr.deprecated th code {
  background: var(--surface-alt);
  border-color: var(--border);
  color: var(--fg-muted);
}
.badge-deprecated {
  display: inline-block; margin-left: 6px;
  padding: 2px 8px; font-size: 0.68rem; font-weight: 600;
  letter-spacing: 0.06em; text-transform: uppercase;
  color: var(--fg-muted);
  background: var(--surface-alt);
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  vertical-align: middle;
}

.users-list {
  list-style: none; padding: 0; margin: 10px 0 0;
  display: flex; flex-wrap: wrap; gap: 8px;
}
.users-list li {
  font-size: 0.9rem;
}
.users-list a {
  display: inline-block;
  padding: 5px 12px;
  color: var(--fg);
  background: var(--surface-alt);
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  font-weight: 550;
  transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease;
}
.users-list a:hover {
  text-decoration: none;
  background: linear-gradient(135deg, rgba(252, 232, 151, 0.4), rgba(244, 189, 55, 0.15));
  border-color: rgba(244, 189, 55, 0.45);
  color: var(--gold-700);
}
@media (prefers-color-scheme: dark) {
  .users-list a:hover {
    background: linear-gradient(135deg, rgba(244, 189, 55, 0.22), rgba(244, 189, 55, 0.06));
    color: var(--gold-100);
  }
}
.matrix tbody th code {
  background: linear-gradient(135deg, rgba(252, 232, 151, 0.45), rgba(244, 189, 55, 0.1));
  border-color: rgba(244, 189, 55, 0.35); color: var(--gold-700);
}
@media (prefers-color-scheme: dark) {
  .matrix tbody th code {
    background: linear-gradient(135deg, rgba(244, 189, 55, 0.2), rgba(244, 189, 55, 0.05));
    color: var(--gold-300);
  }
}

/* Community */
.community {
  display: grid; gap: 32px; align-items: center;
  grid-template-columns: 1.1fr 0.9fr;
}
@media (max-width: 820px) { .community { grid-template-columns: 1fr; } }
.community-right blockquote {
  margin: 0; padding: 28px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius);
  font-size: 1.05rem; color: var(--fg-subtle);
  box-shadow: var(--shadow-sm);
}
.community-right blockquote p { margin: 0; }

/* Footer */
.footer { padding: 64px 0 28px; border-top: 1px solid var(--border); background: var(--surface); }
.footer-inner {
  display: grid; gap: 36px;
  grid-template-columns: 1fr 2fr;
}
@media (max-width: 820px) { .footer-inner { grid-template-columns: 1fr; } }
.foot-brand .brand-name { font-size: 1.2rem; }
.foot-brand p { margin-top: 10px; color: var(--fg-muted); max-width: 320px; }
.foot-cols {
  display: grid; gap: 24px;
  grid-template-columns: repeat(3, minmax(0, 1fr));
}
@media (max-width: 560px) { .foot-cols { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
.foot-cols h4 {
  font-size: 0.8rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--fg-muted);
  margin-bottom: 12px;
}
.foot-cols ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.foot-cols a { color: var(--fg-subtle); font-size: 0.95rem; }
.foot-cols a:hover { color: var(--fg); text-decoration: none; }
.foot-bottom {
  margin-top: 40px; padding-top: 20px; border-top: 1px solid var(--border);
  color: var(--fg-muted); font-size: 0.86rem;
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  * { transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; scroll-behavior: auto; }
}