:root {
  --bg: #0a0a0c;
  --bg-surface: #111114;
  --bg-elevated: #18181c;
  --fg: #e8e6e1;
  --fg-muted: #8a8880;
  --fg-dim: #5a5850;
  --accent: #d4a843;
  --accent-dim: #b8922e;
  --accent-glow: rgba(212, 168, 67, 0.12);
  --border: #2a2a2e;
  --border-light: #1e1e22;
  --mono: 'JetBrains Mono', monospace;
  --sans: 'Space Grotesk', system-ui, sans-serif;
  --radius: 6px;
  --max-w: 1100px;
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  line-height: 1.6;
  overflow-x: hidden;
}

/* ─── NAV ──────────────────────────────────────────────────────────────────── */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 200;
  background: rgba(10, 10, 12, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
}

.nav-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 16px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: inherit;
  flex-shrink: 0;
}

.logo-icon {
  color: var(--accent);
  font-size: 18px;
}

.logo-text {
  font-weight: 600;
  font-size: 17px;
  letter-spacing: -0.02em;
}

/* Desktop nav links */
.nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-link-item {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--fg-muted);
  text-decoration: none;
  letter-spacing: 0.04em;
  transition: color 0.2s;
  white-space: nowrap;
  min-height: 44px;
  display: flex;
  align-items: center;
}
.nav-link-item:hover { color: var(--fg); }
.nav-link-accent { color: var(--accent); }
.nav-link-accent:hover { opacity: 0.85; color: var(--accent); }

.nav-tagline {
  font-size: 13px;
  color: var(--fg-muted);
  font-family: var(--mono);
  letter-spacing: 0.02em;
  white-space: nowrap;
}

/* Hamburger button — hidden on desktop */
.nav-hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
  flex-shrink: 0;
  z-index: 210;
}
.nav-hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--fg);
  border-radius: 2px;
  transition: transform 0.25s, opacity 0.25s;
  transform-origin: center;
}

/* Open state — X icon */
.nav-open .nav-hamburger span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav-open .nav-hamburger span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}
.nav-open .nav-hamburger span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Mobile menu panel */
.nav-mobile-menu {
  display: none;
  flex-direction: column;
  gap: 0;
  background: var(--bg);
  border-top: 1px solid var(--border);
  padding: 8px 0 24px;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, opacity 0.25s ease;
  opacity: 0;
}

.nav-open .nav-mobile-menu {
  max-height: 300px;
  opacity: 1;
}

.nav-mobile-link {
  display: flex;
  align-items: center;
  min-height: 56px;
  padding: 0 24px;
  font-family: var(--mono);
  font-size: 15px;
  color: var(--fg-muted);
  text-decoration: none;
  letter-spacing: 0.04em;
  border-bottom: 1px solid var(--border-light);
  transition: color 0.15s, background 0.15s;
}
.nav-mobile-link:hover { color: var(--fg); background: var(--bg-surface); }
.nav-mobile-link-accent { color: var(--accent); }
.nav-mobile-link-accent:hover { color: var(--accent); opacity: 0.85; }

/* ─── HERO ─────────────────────────────────────────────────────────────────── */
.hero {
  padding: 100px 16px 72px;
  max-width: var(--max-w);
  margin: 0 auto;
}

.hero-inner {
  max-width: 720px;
}

.hero-label {
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.15em;
  color: var(--accent);
  margin-bottom: 20px;
  text-transform: uppercase;
}

.hero-title {
  font-size: clamp(2rem, 7vw, 3.8rem);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 24px;
}

.hero-accent {
  color: var(--accent);
}

.hero-lede {
  font-size: clamp(0.95rem, 2.5vw, 1.1rem);
  color: var(--fg-muted);
  line-height: 1.7;
  max-width: 560px;
  margin-bottom: 40px;
}

.hero-path {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
  font-family: var(--mono);
  font-size: 13px;
  padding: 14px 18px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  width: fit-content;
  max-width: 100%;
  overflow-x: auto;
}

.path-segment {
  color: var(--fg-muted);
  padding: 2px 8px;
  border-radius: 4px;
  transition: color 0.2s;
  white-space: nowrap;
}

.path-sep {
  color: var(--fg-dim);
  flex-shrink: 0;
}

.path-active {
  color: var(--accent);
  background: var(--accent-glow);
}

/* ─── HIERARCHY ────────────────────────────────────────────────────────────── */
.hierarchy {
  padding: 72px 16px;
  background: var(--bg-surface);
  border-top: 1px solid var(--border-light);
  border-bottom: 1px solid var(--border-light);
}

.hierarchy-inner {
  max-width: var(--max-w);
  margin: 0 auto;
}

.section-label {
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.15em;
  color: var(--accent);
  margin-bottom: 16px;
  text-transform: uppercase;
}

.section-title {
  font-size: clamp(1.4rem, 4vw, 2.2rem);
  font-weight: 600;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}

.section-desc {
  font-size: 1rem;
  color: var(--fg-muted);
  max-width: 520px;
  margin-bottom: 48px;
}

.pyramid {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.pyramid-level {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.pyramid-box {
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 500;
  padding: 10px 16px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--fg);
  white-space: nowrap;
}

.pyramid-more {
  color: var(--fg-dim);
  border-style: dashed;
}

.pyramid-l1 .pyramid-box {
  background: var(--accent-glow);
  border-color: var(--accent-dim);
  color: var(--accent);
  font-size: 13px;
  padding: 12px 24px;
}

/* ─── FEATURES ─────────────────────────────────────────────────────────────── */
.features {
  padding: 72px 16px;
}

.features-inner {
  max-width: var(--max-w);
  margin: 0 auto;
}

.feature-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.feature-card {
  padding: 28px 24px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color 0.3s;
}

.feature-card:hover {
  border-color: var(--accent-dim);
}

.feature-num {
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 500;
  color: var(--accent);
  margin-bottom: 16px;
  letter-spacing: 0.05em;
}

.feature-title {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 10px;
  letter-spacing: -0.01em;
}

.feature-desc {
  font-size: 0.9rem;
  color: var(--fg-muted);
  line-height: 1.65;
}

.feature-desc code {
  font-family: var(--mono);
  font-size: 0.82rem;
  background: var(--bg-elevated);
  padding: 2px 6px;
  border-radius: 3px;
  color: var(--accent);
}

/* ─── STATS ────────────────────────────────────────────────────────────────── */
.stats {
  padding: 56px 16px;
  background: var(--bg-surface);
  border-top: 1px solid var(--border-light);
  border-bottom: 1px solid var(--border-light);
}

.stats-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px 16px;
  text-align: center;
}

.stat {}

.stat-divider { display: none; }

.stat-number {
  font-family: var(--mono);
  font-size: clamp(1.4rem, 5vw, 2rem);
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 6px;
}

.stat-label {
  font-size: 0.82rem;
  color: var(--fg-muted);
  letter-spacing: 0.02em;
}

/* ─── CLOSING ──────────────────────────────────────────────────────────────── */
.closing {
  padding: 80px 16px;
  text-align: center;
}

.closing-inner {
  max-width: 680px;
  margin: 0 auto;
}

.closing-title {
  font-size: clamp(1.3rem, 4vw, 2.2rem);
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.3;
  margin-bottom: 20px;
}

.closing-desc {
  font-size: 1rem;
  color: var(--fg-muted);
  line-height: 1.7;
  margin-bottom: 40px;
}

.closing-badge {
  display: inline-block;
  font-family: var(--mono);
  font-size: 13px;
  font-weight: 500;
  color: var(--accent);
  padding: 12px 28px;
  border: 1px solid var(--accent-dim);
  border-radius: var(--radius);
  background: var(--accent-glow);
  letter-spacing: 0.05em;
}

/* ─── FOOTER ───────────────────────────────────────────────────────────────── */
.footer {
  padding: 24px 16px;
  border-top: 1px solid var(--border-light);
}

.footer-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 13px;
  color: var(--fg-dim);
  flex-wrap: wrap;
  gap: 8px;
}

.footer-left {
  display: flex;
  align-items: center;
  gap: 8px;
}

.footer-link {
  color: var(--fg-muted);
  text-decoration: none;
  transition: color 0.2s;
}
.footer-link:hover { color: var(--accent); }

/* ─── RESPONSIVE: 375px (primary mobile target) ────────────────────────────── */
@media (max-width: 640px) {
  /* Show hamburger, hide desktop links */
  .nav-hamburger { display: flex; }
  .nav-links { display: none; }
  .nav-mobile-menu { display: flex; }

  .hero { padding: 84px 16px 56px; }
  .hero-path { font-size: 11px; padding: 10px 14px; }

  .hierarchy { padding: 56px 16px; }
  .section-desc { margin-bottom: 32px; }

  .features { padding: 56px 16px; }

  .stats { padding: 48px 16px; }

  .closing { padding: 64px 16px; }
}

/* ─── RESPONSIVE: tablet / 768px+ ─────────────────────────────────────────── */
@media (min-width: 641px) and (max-width: 900px) {
  .nav-hamburger { display: flex; }
  .nav-links { display: none; }
  .nav-mobile-menu { display: flex; }

  .hero { padding: 100px 24px 80px; }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-inner {
    grid-template-columns: repeat(4, 1fr);
    gap: 0;
  }
  .stat-divider { display: block; width: 1px; height: 48px; background: var(--border); }
}

/* ─── RESPONSIVE: desktop / 901px+ ────────────────────────────────────────── */
@media (min-width: 901px) {
  .nav-inner { padding: 0 24px; }
  .nav-hamburger { display: none; }
  .nav-links { display: flex; }
  .nav-mobile-menu { display: none !important; }
  .nav-tagline { display: block; }

  .hero { padding: 140px 24px 100px; }

  .hierarchy { padding: 100px 24px; }
  .features { padding: 100px 24px; }
  .stats { padding: 64px 24px; }
  .stats-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
  }
  .stat { flex: 1; }
  .stat-divider { display: block; width: 1px; height: 48px; background: var(--border); }

  .closing { padding: 120px 24px; }
  .feature-grid { grid-template-columns: repeat(2, 1fr); gap: 24px; }
  .feature-card { padding: 36px 32px; }
}