:root {
  --bg: #09090b;
  --bg-subtle: #0f1014;
  --panel: #141419;
  --panel-hover: #1a1a21;
  --border: #23252e;
  --border-light: #2e303a;
  --fg: #ececf1;
  --fg-secondary: #a1a1aa;
  --muted: #71717a;
  --accent: #60a5fa;
  --accent-dim: rgba(96, 165, 250, 0.12);
  --green: #4ade80;
  --green-dim: rgba(74, 222, 128, 0.12);
  --amber: #fbbf24;
  --amber-dim: rgba(251, 191, 36, 0.12);
  --red: #f87171;
  --red-dim: rgba(248, 113, 113, 0.1);
  --gray: #71717a;
  --mono: "JetBrains Mono", "Cascadia Code", Consolas, monospace;
  --sans: "Inter", system-ui, -apple-system, sans-serif;
  --radius: 12px;
  --radius-sm: 8px;
  --max-w: 1120px;
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.container { max-width: var(--max-w); margin: 0 auto; padding: 0 24px; }

/* ─── Topnav ─── */
.topnav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(9, 9, 11, 0.85);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
}
.topnav-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
}
.logo {
  font-family: var(--mono);
  font-size: 18px;
  font-weight: 600;
  color: var(--fg);
  text-decoration: none;
}
.logo span { color: var(--accent); }
.nav-links { display: flex; align-items: center; gap: 24px; }
.nav-links a {
  color: var(--fg-secondary);
  text-decoration: none;
  font-size: 13px;
  font-weight: 500;
  transition: color 0.15s;
}
.nav-links a:hover { color: var(--fg); }
.nav-gh {
  background: var(--panel);
  border: 1px solid var(--border);
  padding: 6px 14px;
  border-radius: var(--radius-sm);
}
.nav-gh:hover { border-color: var(--accent); color: var(--accent) !important; }

/* ─── Hero ─── */
.hero {
  padding: 100px 24px 80px;
  text-align: center;
  background: radial-gradient(ellipse 70% 50% at 50% 0%, rgba(96, 165, 250, 0.06) 0%, transparent 100%);
}
.hero-inner { max-width: 780px; margin: 0 auto; }
.hero-badge {
  display: inline-block;
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 500;
  color: var(--accent);
  background: var(--accent-dim);
  padding: 5px 14px;
  border-radius: 999px;
  margin-bottom: 28px;
  letter-spacing: 0.3px;
}
.hero h1 {
  font-size: clamp(32px, 5vw, 52px);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
}
.hero-sub {
  font-size: 17px;
  color: var(--fg-secondary);
  max-width: 620px;
  margin: 0 auto 36px;
  line-height: 1.7;
}
.hero-sub strong { color: var(--fg); font-weight: 600; }
.hero-actions { display: flex; justify-content: center; gap: 12px; margin-bottom: 56px; }

.btn {
  display: inline-flex;
  align-items: center;
  font-size: 14px;
  font-weight: 600;
  padding: 11px 24px;
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: all 0.15s;
  cursor: pointer;
}
.btn-primary {
  background: var(--accent);
  color: #0b1016;
}
.btn-primary:hover { filter: brightness(1.1); }
.btn-outline {
  background: transparent;
  color: var(--fg-secondary);
  border: 1px solid var(--border);
}
.btn-outline:hover { border-color: var(--fg-secondary); color: var(--fg); }

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 48px;
  flex-wrap: wrap;
}
.stat { display: flex; flex-direction: column; align-items: center; }
.stat-num {
  font-family: var(--mono);
  font-size: 28px;
  font-weight: 700;
  color: var(--fg);
}
.stat-label {
  font-size: 12px;
  color: var(--muted);
  margin-top: 4px;
}

/* ─── Sections ─── */
.section { padding: 80px 0; }
.section-dark { background: var(--bg-subtle); }
.section-label {
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 500;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 1.5px;
  margin-bottom: 12px;
}
.section h2 {
  font-size: clamp(24px, 3.5vw, 36px);
  font-weight: 700;
  letter-spacing: -0.015em;
  margin-bottom: 16px;
}
.section-desc {
  color: var(--fg-secondary);
  max-width: 640px;
  margin-bottom: 48px;
  font-size: 16px;
}

/* ─── Compare grid ─── */
.compare-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.compare-card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
}
.compare-header {
  font-weight: 600;
  font-size: 16px;
  margin-bottom: 16px;
}
.compare-card ul {
  list-style: none;
  padding: 0;
  margin: 0 0 20px;
}
.compare-card li {
  padding: 6px 0;
  font-size: 14px;
  color: var(--fg-secondary);
  position: relative;
  padding-left: 20px;
}
.compare-card li::before {
  position: absolute;
  left: 0;
  top: 6px;
}
.compare-card.bad li::before { content: "✗"; color: var(--red); }
.compare-card.good li::before { content: "✓"; color: var(--green); }
.compare-result {
  font-family: var(--mono);
  font-size: 22px;
  font-weight: 700;
}
.compare-card.bad .compare-result { color: var(--red); }
.compare-card.good .compare-result { color: var(--green); }
.compare-card.bad { border-color: rgba(248, 113, 113, 0.2); }
.compare-card.good { border-color: rgba(74, 222, 128, 0.2); }

/* ─── Features grid ─── */
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.feature-card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  transition: border-color 0.15s;
}
.feature-card:hover { border-color: var(--border-light); }
.feature-icon { font-size: 24px; margin-bottom: 12px; }
.feature-card h3 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 8px;
}
.feature-card p {
  font-size: 13px;
  color: var(--fg-secondary);
  line-height: 1.55;
}

/* ─── Pipeline ─── */
.pipeline {
  display: flex;
  align-items: flex-start;
  gap: 0;
}
.pipe-step {
  flex: 1;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
}
.pipe-arrow {
  display: flex;
  align-items: center;
  padding: 0 12px;
  font-size: 20px;
  color: var(--muted);
  margin-top: 36px;
}
.pipe-num {
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-dim);
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  margin-bottom: 12px;
}
.pipe-step h3 { font-size: 15px; font-weight: 600; margin-bottom: 8px; }
.pipe-step p { font-size: 13px; color: var(--fg-secondary); line-height: 1.5; }

/* ─── Benchmark table ─── */
.table-wrap {
  overflow-x: auto;
  margin-bottom: 16px;
}
table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}
th {
  text-align: left;
  font-weight: 600;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--muted);
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
}
td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--border);
  color: var(--fg-secondary);
  font-family: var(--mono);
  font-size: 13px;
}
td:first-child { font-family: var(--sans); font-size: 14px; color: var(--fg); }
.highlight-row td {
  background: var(--accent-dim);
  color: var(--fg);
}
.table-note { font-size: 13px; color: var(--muted); max-width: 680px; }

/* ─── Demo section ─── */
.demo-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  min-height: 520px;
}
.demo-chat-col {
  display: flex;
  flex-direction: column;
  min-height: 0;
}
.demo-status { margin-bottom: 12px; }

.pill {
  font-family: var(--mono);
  font-size: 11px;
  padding: 4px 10px;
  border-radius: 999px;
  border: 1px solid var(--border);
  color: var(--muted);
}
.pill.ok { color: var(--green); border-color: var(--green); }
.pill.err { color: var(--red); border-color: var(--red); }
.pill.pending { color: var(--muted); }

.samples { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 12px; }
.samples button {
  background: var(--panel);
  border: 1px solid var(--border);
  color: var(--muted);
  font-size: 11px;
  padding: 5px 10px;
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.15s;
}
.samples button:hover { color: var(--fg); border-color: var(--accent); }

.chat {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding-right: 4px;
  min-height: 280px;
  max-height: 420px;
}
.msg { max-width: 92%; }
.msg.q {
  align-self: flex-end;
  background: var(--accent);
  color: #0b1016;
  padding: 8px 14px;
  border-radius: 12px 12px 2px 12px;
  font-size: 14px;
}
.msg.a {
  align-self: flex-start;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px 12px 12px 2px;
  padding: 12px 14px;
  font-size: 13px;
  line-height: 1.5;
  white-space: pre-wrap;
  font-family: var(--mono);
}
.msg.a .badge {
  display: inline-block;
  font-size: 10px;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: 4px;
  margin-bottom: 8px;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}
.badge.FAST { background: var(--green-dim); color: var(--green); }
.badge.DEEP { background: var(--amber-dim); color: var(--amber); }
.badge.ABSTAIN { background: rgba(113, 113, 122, 0.2); color: var(--gray); }
.probe-row {
  font-size: 11px;
  color: var(--muted);
  margin-bottom: 8px;
  font-family: var(--mono);
}
.citations {
  margin-top: 10px;
  border-top: 1px dashed var(--border);
  padding-top: 8px;
  font-size: 12px;
  color: var(--muted);
}
.citations .cite { margin: 4px 0; }
.citations .cite-key { color: var(--accent); font-family: var(--mono); font-size: 11px; }
.citations .quote { font-style: italic; }
.msg.err {
  background: var(--red-dim);
  border: 1px solid var(--red);
  color: var(--red);
}

#ask-form { display: flex; gap: 8px; margin-top: 12px; }
#ask-form input {
  flex: 1;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--fg);
  padding: 11px 14px;
  font-size: 14px;
  font-family: var(--sans);
  outline: none;
  transition: border-color 0.15s;
}
#ask-form input:focus { border-color: var(--accent); }
#ask-form button {
  background: var(--accent);
  border: none;
  color: #0b1016;
  font-weight: 600;
  padding: 11px 20px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 14px;
  transition: filter 0.15s;
}
#ask-form button:hover { filter: brightness(1.1); }
#ask-form button:disabled { opacity: 0.5; cursor: wait; }

/* ─── Graph panel ─── */
.demo-graph-col {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  display: flex;
  flex-direction: column;
  min-height: 0;
}
.graph-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 10px;
  font-size: 13px;
  font-weight: 600;
  color: var(--fg-secondary);
}
.graph-meta { font-family: var(--mono); font-size: 11px; color: var(--muted); }
#graph { flex: 1; min-height: 0; border-radius: var(--radius-sm); background: var(--bg); }
.legend {
  display: flex;
  gap: 14px;
  font-size: 11px;
  color: var(--muted);
  padding-top: 10px;
  flex-wrap: wrap;
}
.dot { display: inline-block; width: 8px; height: 8px; border-radius: 50%; margin-right: 4px; vertical-align: middle; }
.dot.entity { background: var(--accent); }
.dot.active { background: var(--green); }
.dot.superseded { background: var(--gray); }
.edge { display: inline-block; width: 16px; height: 0; border-top: 2px dashed; margin-right: 4px; vertical-align: middle; }
.edge.sup { border-color: var(--amber); }
.edge.con { border-color: var(--red); }

/* ─── Footer ─── */
footer {
  border-top: 1px solid var(--border);
  padding: 28px 0;
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.footer-brand { display: flex; align-items: center; gap: 16px; }
.footer-tagline { color: var(--muted); font-size: 13px; }
.footer-links { display: flex; align-items: center; gap: 20px; }
.footer-links a {
  color: var(--fg-secondary);
  text-decoration: none;
  font-size: 13px;
}
.footer-links a:hover { color: var(--fg); }
.footer-license { color: var(--muted); font-size: 12px; }

/* ─── Responsive ─── */
@media (max-width: 900px) {
  .compare-grid, .demo-layout { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: 1fr 1fr; }
  .pipeline { flex-direction: column; }
  .pipe-arrow { transform: rotate(90deg); padding: 8px 0; margin-top: 0; }
  .hero-stats { gap: 28px; }
  .nav-links a:not(.nav-gh) { display: none; }
}
@media (max-width: 600px) {
  .features-grid { grid-template-columns: 1fr; }
  .footer-inner { flex-direction: column; gap: 12px; text-align: center; }
}