/* ============================================================
   VeriLog — Professional Design System
   ============================================================ */

:root {
  /* Color Palette */
  --ink:          #0f172a;
  --ink-soft:     #475569;
  --ink-muted:    #94a3b8;
  --surface:      #ffffff;
  --surface-alt:  #f8fafc;
  --surface-dark: #0f172a;
  --border:       #e2e8f0;
  --border-light: #f1f5f9;

  /* Brand Colors */
  --brand:        #0d9488;
  --brand-light:  #ccfbf1;
  --brand-dark:   #115e59;
  --accent:       #f59e0b;
  --accent-light: #fef3c7;

  /* Status Colors */
  --green:        #10b981;
  --blue:         #3b82f6;
  --orange:       #f97316;
  --purple:       #8b5cf6;

  /* Shadows */
  --shadow-sm:    0 1px 2px rgba(0,0,0,0.05);
  --shadow-md:    0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
  --shadow-lg:    0 10px 25px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.04);
  --shadow-xl:    0 20px 50px -12px rgba(0,0,0,0.15);

  /* Typography */
  --font-sans:    'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono:    'JetBrains Mono', 'Fira Code', 'SF Mono', monospace;

  /* Spacing */
  --nav-height:   72px;
  --section-pad:  96px;
  --container:    1200px;

  /* Transitions */
  --ease:         cubic-bezier(0.4, 0, 0.2, 1);
}

/* ---- Reset ---- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: var(--nav-height); }
body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--ink);
  background: var(--surface);
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
h1, h2, h3, h4, p, ul { margin: 0; }
img { max-width: 100%; display: block; }
button { font: inherit; cursor: pointer; }

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

/* ============================================================
   NAVIGATION
   ============================================================ */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--nav-height);
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px) saturate(180%);
  border-bottom: 1px solid var(--border);
  transition: box-shadow 0.3s var(--ease);
}
.navbar.scrolled { box-shadow: var(--shadow-md); }

.nav-container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 1.2rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--ink);
}
.brand-icon {
  color: var(--brand);
  font-size: 1.1rem;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-group {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-group > a,
.dropdown-trigger {
  padding: 8px 14px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--ink-soft);
  border: none;
  background: none;
  border-radius: 8px;
  transition: all 0.2s var(--ease);
}
.nav-group > a:hover,
.dropdown-trigger:hover {
  color: var(--ink);
  background: var(--surface-alt);
}

.caret { font-size: 0.7em; margin-left: 2px; }

/* Dropdown */
.dropdown { position: relative; }
.dropdown-menu {
  display: none;
  position: absolute;
  top: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  min-width: 200px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 8px;
  box-shadow: var(--shadow-lg);
  z-index: 100;
}
.dropdown:hover .dropdown-menu,
.dropdown:focus-within .dropdown-menu { display: block; }

.dropdown-wide {
  min-width: 320px;
  display: none;
  padding: 12px 16px;
}
.dropdown:hover .dropdown-wide,
.dropdown:focus-within .dropdown-wide { display: block; }

.dropdown-menu a {
  display: block;
  padding: 8px 12px;
  font-size: 0.88rem;
  color: var(--ink-soft);
  border-radius: 8px;
  transition: all 0.15s var(--ease);
}
.dropdown-menu a:hover {
  color: var(--ink);
  background: var(--surface-alt);
}

.dropdown-heading {
  display: block;
  padding: 4px 12px 6px;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-muted);
}
.dropdown-divider {
  height: 1px;
  background: var(--border);
  margin: 8px 0;
}
.dropdown-section { margin-bottom: 4px; }

.nav-cta {
  margin-left: 16px;
  padding: 8px 18px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--surface);
  background: var(--ink);
  border-radius: 8px;
  transition: all 0.2s var(--ease);
}
.nav-cta:hover { background: #1e293b; }

/* Mobile Nav Toggle */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  background: none;
  border: none;
}
.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--ink);
  border-radius: 2px;
  transition: all 0.3s var(--ease);
}

/* ============================================================
   HERO
   ============================================================ */
.hero {
  padding-top: calc(var(--nav-height) + 80px);
  padding-bottom: 80px;
  background:
    radial-gradient(ellipse 80% 60% at 20% 40%, rgba(13,148,136,0.06), transparent),
    radial-gradient(ellipse 60% 50% at 80% 20%, rgba(245,158,11,0.05), transparent),
    linear-gradient(180deg, var(--surface) 0%, var(--surface-alt) 100%);
}

.hero .container {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 64px;
  align-items: center;
}

.hero-badge {
  display: inline-block;
  padding: 6px 16px;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--brand-dark);
  background: var(--brand-light);
  border-radius: 999px;
  margin-bottom: 24px;
}

.hero h1 {
  font-size: clamp(2.8rem, 5.5vw, 5rem);
  line-height: 1.05;
  letter-spacing: -0.04em;
  font-weight: 800;
}
.hero h1 em {
  font-style: normal;
  color: var(--brand);
}

.hero-lead {
  margin-top: 20px;
  font-size: 1.12rem;
  line-height: 1.7;
  color: var(--ink-soft);
  max-width: 540px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

/* Trust Stack Visual */
.trust-stack {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.trust-layer {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 20px 24px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  box-shadow: var(--shadow-sm);
  transition: all 0.3s var(--ease);
}
.trust-layer:hover {
  box-shadow: var(--shadow-md);
  transform: translateX(4px);
}
.layer-num {
  font-size: 0.78rem;
  font-weight: 800;
  color: var(--ink-muted);
  letter-spacing: 0.06em;
  font-family: var(--font-mono);
}
.layer-label {
  flex: 1;
  font-weight: 600;
  font-size: 0.95rem;
}
.layer-status {
  padding: 4px 12px;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  border-radius: 999px;
}
.layer-status.shipped { background: #d1fae5; color: #065f46; }
.layer-status.active  { background: #dbeafe; color: #1e40af; }
.layer-status.upcoming { background: var(--accent-light); color: #92400e; }

/* ============================================================
   BUTTONS
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 24px;
  font-size: 0.92rem;
  font-weight: 600;
  border-radius: 10px;
  border: none;
  cursor: pointer;
  transition: all 0.2s var(--ease);
}
.btn-primary {
  background: var(--ink);
  color: var(--surface);
}
.btn-primary:hover { background: #1e293b; transform: translateY(-1px); box-shadow: var(--shadow-md); }
.btn-outline {
  background: var(--surface);
  color: var(--ink);
  border: 1.5px solid var(--border);
}
.btn-outline:hover { border-color: var(--ink-muted); background: var(--surface-alt); }
.btn-ghost {
  background: rgba(255,255,255,0.15);
  color: var(--surface);
  border: 1.5px solid rgba(255,255,255,0.25);
}
.btn-ghost:hover { background: rgba(255,255,255,0.22); }
.btn-lg { padding: 14px 32px; font-size: 1rem; }

/* ============================================================
   STATS BANNER
   ============================================================ */
.stats-banner {
  padding: 48px 0;
  background: var(--surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
.stats-row {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 48px;
}
.stat { text-align: center; }
.stat-number {
  display: block;
  font-size: 2.8rem;
  font-weight: 800;
  letter-spacing: -0.04em;
  color: var(--ink);
  line-height: 1;
}
.stat-desc {
  display: block;
  margin-top: 8px;
  font-size: 0.85rem;
  color: var(--ink-muted);
  line-height: 1.4;
}
.stat-divider {
  width: 1px;
  height: 48px;
  background: var(--border);
}

/* ============================================================
   SECTIONS
   ============================================================ */
.section {
  padding: var(--section-pad) 0;
}
.section-alt {
  background: var(--surface-alt);
}
.section-dark {
  background: var(--surface-dark);
  color: var(--surface);
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 56px;
}
.section-header.light .section-tag { background: rgba(13,148,136,0.15); color: #5eead4; }
.section-header.light .section-lead { color: var(--ink-muted); }

.section-tag {
  display: inline-block;
  padding: 4px 14px;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--brand-dark);
  background: var(--brand-light);
  border-radius: 999px;
  margin-bottom: 16px;
}
.section-header h2 {
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.1;
  letter-spacing: -0.03em;
  font-weight: 800;
}
.section-lead {
  margin-top: 16px;
  font-size: 1.05rem;
  line-height: 1.7;
  color: var(--ink-soft);
}

/* ============================================================
   FEATURES GRID
   ============================================================ */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.feature-card {
  padding: 32px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  transition: all 0.3s var(--ease);
}
.feature-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}
.feature-icon {
  font-size: 1.8rem;
  margin-bottom: 16px;
}
.feature-card h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 8px;
}
.feature-card p {
  font-size: 0.9rem;
  color: var(--ink-soft);
  line-height: 1.6;
}

/* ============================================================
   ARCHITECTURE DIAGRAM
   ============================================================ */
.arch-diagram {
  max-width: 800px;
  margin: 0 auto;
}
.arch-row {
  display: flex;
  gap: 16px;
  justify-content: center;
}
.arch-row-libs { gap: 12px; }

.arch-box {
  padding: 24px 32px;
  border-radius: 14px;
  text-align: center;
  border: 1.5px solid var(--border);
  flex: 1;
  max-width: 280px;
  transition: all 0.3s var(--ease);
}
.arch-box:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }

.arch-binary  { background: var(--ink); color: var(--surface); border-color: var(--ink); max-width: 100%; }
.arch-core    { background: #ecfdf5; border-color: #a7f3d0; }
.arch-license { background: #eff6ff; border-color: #bfdbfe; }
.arch-enterprise { background: #fef3c7; border-color: #fde68a; }
.arch-storage { background: var(--surface-alt); max-width: 100%; }

.arch-title {
  font-size: 0.95rem;
  font-weight: 700;
  font-family: var(--font-mono);
}
.arch-desc {
  font-size: 0.8rem;
  margin-top: 6px;
  color: var(--ink-soft);
}
.arch-binary .arch-desc { color: var(--ink-muted); }

.arch-connector {
  width: 2px;
  height: 24px;
  background: var(--border);
  margin: 0 auto;
}

/* ============================================================
   TWO COLUMN LAYOUTS
   ============================================================ */
.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}
.two-col.reverse { direction: rtl; }
.two-col.reverse > * { direction: ltr; }

.col-text h2 {
  font-size: clamp(1.8rem, 3.5vw, 2.5rem);
  line-height: 1.1;
  letter-spacing: -0.03em;
  font-weight: 800;
  margin-top: 12px;
}
.col-text > p {
  margin-top: 16px;
  font-size: 1rem;
  line-height: 1.7;
  color: var(--ink-soft);
}

.check-list {
  margin-top: 20px;
  padding: 0;
  list-style: none;
}
.check-list li {
  position: relative;
  padding: 6px 0 6px 28px;
  font-size: 0.92rem;
  color: var(--ink-soft);
}
.check-list li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--green);
  font-weight: 700;
}

/* Threat Card */
.threat-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 32px;
  box-shadow: var(--shadow-md);
}
.threat-card h4 {
  font-size: 0.88rem;
  font-weight: 700;
  margin-bottom: 20px;
  color: var(--ink);
}
.threat-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 0;
  font-size: 0.88rem;
  color: var(--ink-soft);
  border-top: 1px solid var(--border-light);
}
.threat-icon {
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  font-size: 0.7rem;
  flex-shrink: 0;
}
.threat-covered { background: #d1fae5; color: #065f46; }
.threat-future  { background: var(--accent-light); color: #92400e; }

/* ============================================================
   PRIVACY / DP VISUAL
   ============================================================ */
.dp-visual {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 40px 32px;
  box-shadow: var(--shadow-md);
}
.dp-pipeline {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
}
.dp-stage {
  text-align: center;
  padding: 20px 16px;
  border-radius: 12px;
  background: var(--surface-alt);
  border: 1px solid var(--border);
  min-width: 120px;
}
.dp-stage-highlight {
  background: var(--brand-light);
  border-color: #99f6e4;
}
.dp-stage-num {
  display: block;
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--brand);
}
.dp-stage-label {
  display: block;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--ink-soft);
  margin-top: 4px;
}
.dp-arrow {
  font-size: 1.5rem;
  color: var(--ink-muted);
}
.dp-note {
  text-align: center;
  margin-top: 20px;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--brand);
  letter-spacing: 0.02em;
}

/* ============================================================
   MERKLE FEATURES
   ============================================================ */
.merkle-features {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.merkle-card {
  text-align: center;
  padding: 32px 24px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  transition: all 0.3s var(--ease);
}
.merkle-card:hover { box-shadow: var(--shadow-md); transform: translateY(-2px); }
.merkle-card h4 {
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--ink-muted);
  margin-bottom: 12px;
}
.merkle-metric {
  font-size: 1.6rem;
  font-weight: 800;
  font-family: var(--font-mono);
  color: var(--brand);
  margin-bottom: 12px;
}
.merkle-card p {
  font-size: 0.85rem;
  color: var(--ink-soft);
  line-height: 1.5;
}

/* ============================================================
   RESEARCH PILLARS
   ============================================================ */
.research-pillars {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}
.pillar {
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 16px;
  overflow: hidden;
}
.pillar-header {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 20px 24px;
  border-bottom: 1px solid rgba(255,255,255,0.08);
}
.pillar-icon { font-size: 1.3rem; }
.pillar-header h3 {
  font-size: 1rem;
  font-weight: 700;
}

.track-list { padding: 8px; }

.track-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 12px 16px;
  border-radius: 10px;
  transition: background 0.2s var(--ease);
  cursor: default;
}
.track-item:hover { background: rgba(255,255,255,0.05); }

.track-id {
  font-size: 0.72rem;
  font-weight: 700;
  font-family: var(--font-mono);
  color: var(--brand);
  padding: 2px 8px;
  background: rgba(13,148,136,0.15);
  border-radius: 6px;
  white-space: nowrap;
  margin-top: 2px;
}
.track-info { flex: 1; }
.track-name {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--surface);
}
.track-desc {
  font-size: 0.78rem;
  color: var(--ink-muted);
  margin-top: 2px;
  line-height: 1.4;
}

/* ============================================================
   NOVELTY WEDGES
   ============================================================ */
.wedge-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}
.wedge-card {
  padding: 32px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  transition: all 0.3s var(--ease);
  position: relative;
  overflow: hidden;
}
.wedge-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--brand), var(--accent));
}
.wedge-card:hover { box-shadow: var(--shadow-lg); transform: translateY(-2px); }
.wedge-letter {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  font-size: 0.85rem;
  font-weight: 800;
  color: var(--brand-dark);
  background: var(--brand-light);
  border-radius: 10px;
  margin-bottom: 16px;
}
.wedge-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 10px;
}
.wedge-card p {
  font-size: 0.9rem;
  color: var(--ink-soft);
  line-height: 1.6;
}
.wedge-status {
  display: inline-block;
  margin-top: 16px;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--brand);
}

/* ============================================================
   TIMELINE / ROADMAP
   ============================================================ */
.timeline {
  position: relative;
  max-width: 700px;
  margin: 0 auto;
  padding-left: 40px;
}
.timeline::before {
  content: '';
  position: absolute;
  left: 15px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--border);
}

.timeline-item {
  position: relative;
  padding-bottom: 40px;
}
.timeline-item:last-child { padding-bottom: 0; }

.timeline-marker {
  position: absolute;
  left: -33px;
  top: 4px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--border);
  border: 3px solid var(--surface-alt);
}
.timeline-item.done .timeline-marker   { background: var(--green); }
.timeline-item.active .timeline-marker { background: var(--blue); box-shadow: 0 0 0 4px rgba(59,130,246,0.2); }

.timeline-content {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 24px;
}
.timeline-phase {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-muted);
  margin-bottom: 6px;
}
.timeline-content h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 12px;
}
.timeline-content ul {
  padding-left: 18px;
  font-size: 0.88rem;
  color: var(--ink-soft);
  line-height: 1.8;
  list-style: none;
}
.timeline-content li { padding-left: 1em; text-indent: -1em; }
.timeline-content li::before { content: "—  "; color: var(--ink-muted); }
.timeline-content li.done-item { color: var(--green); }
.timeline-content li.done-item::before { content: ""; }
.timeline-badge {
  display: inline-block;
  margin-top: 14px;
  padding: 4px 12px;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  border-radius: 999px;
  background: var(--surface-alt);
  color: var(--ink-muted);
}
.badge-done   { background: #d1fae5; color: #065f46; }
.badge-active { background: #dbeafe; color: #1e40af; }

/* ============================================================
   CTA FOOTER
   ============================================================ */
.cta-footer {
  text-align: center;
  max-width: 600px;
  margin: 0 auto;
  padding: 40px 0;
}
.cta-footer h2 {
  font-size: clamp(1.8rem, 3vw, 2.5rem);
  font-weight: 800;
  letter-spacing: -0.03em;
}
.cta-footer p {
  margin-top: 16px;
  font-size: 1rem;
  color: var(--ink-muted);
  line-height: 1.6;
}
.cta-actions {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-top: 32px;
}

/* ============================================================
   SITE FOOTER
   ============================================================ */
.site-footer {
  background: var(--surface-alt);
  border-top: 1px solid var(--border);
  padding: 56px 0 32px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
}
.footer-brand p {
  margin-top: 12px;
  font-size: 0.85rem;
  color: var(--ink-muted);
  line-height: 1.5;
}
.footer-links h4 {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-muted);
  margin-bottom: 16px;
}
.footer-links a {
  display: block;
  padding: 4px 0;
  font-size: 0.88rem;
  color: var(--ink-soft);
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--ink); }

.footer-bottom {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  text-align: center;
}
.footer-bottom p {
  font-size: 0.82rem;
  color: var(--ink-muted);
}

/* ============================================================
   DOCS PAGE
   ============================================================ */
.docs-layout {
  padding-top: calc(var(--nav-height) + 32px);
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 48px;
  min-height: 100vh;
}
.docs-sidebar {
  position: sticky;
  top: calc(var(--nav-height) + 32px);
  max-height: calc(100vh - var(--nav-height) - 64px);
  overflow-y: auto;
  padding-bottom: 48px;
}
.docs-sidebar h4 {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-muted);
  margin: 24px 0 8px;
}
.docs-sidebar h4:first-child { margin-top: 0; }

.docs-sidebar a {
  display: block;
  padding: 6px 12px;
  font-size: 0.88rem;
  color: var(--ink-soft);
  border-radius: 6px;
  border-left: 2px solid transparent;
  transition: all 0.15s;
}
.docs-sidebar a:hover {
  color: var(--ink);
  background: var(--surface-alt);
}
.docs-sidebar a.active {
  color: var(--brand);
  border-left-color: var(--brand);
  background: var(--brand-light);
}

.docs-content {
  padding-bottom: 96px;
  max-width: 800px;
}
.docs-content h1 {
  font-size: 2rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 32px;
}
.docs-content h2 {
  font-size: 1.4rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 48px 0 16px;
}
.docs-content h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin: 32px 0 12px;
}
.docs-content p {
  font-size: 0.95rem;
  color: var(--ink-soft);
  line-height: 1.7;
  margin: 12px 0;
}
.docs-content ul, .docs-content ol {
  padding-left: 24px;
  font-size: 0.95rem;
  color: var(--ink-soft);
  line-height: 1.8;
}
.docs-content code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  background: var(--surface-alt);
  padding: 2px 6px;
  border-radius: 4px;
  border: 1px solid var(--border);
}
.docs-content pre {
  background: var(--surface-dark);
  color: #e2e8f0;
  padding: 24px;
  border-radius: 12px;
  overflow-x: auto;
  font-size: 0.85rem;
  line-height: 1.6;
  margin: 20px 0;
}
.docs-content pre code {
  background: none;
  padding: 0;
  border: none;
  color: inherit;
}

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 1024px) {
  .hero .container { grid-template-columns: 1fr; gap: 40px; }
  .hero-visual { display: none; }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .research-pillars { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .docs-layout { grid-template-columns: 1fr; }
  .docs-sidebar { display: none; }
}

@media (max-width: 768px) {
  :root { --section-pad: 64px; }

  .nav-toggle { display: flex; }
  .nav-menu {
    display: none;
    position: absolute;
    top: var(--nav-height);
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    padding: 16px 24px;
    box-shadow: var(--shadow-lg);
  }
  .nav-menu.open { display: flex; }
  .nav-group { flex-direction: column; align-items: stretch; gap: 0; }
  .nav-cta { margin: 12px 0 0; text-align: center; }
  .dropdown-menu, .dropdown-wide {
    position: static;
    transform: none;
    box-shadow: none;
    border: none;
    padding: 0 0 0 16px;
  }

  .hero { padding-top: calc(var(--nav-height) + 40px); padding-bottom: 48px; }
  .hero h1 { font-size: 2.4rem; }

  .stats-row { flex-wrap: wrap; gap: 24px; }
  .stat-divider { display: none; }

  .features-grid { grid-template-columns: 1fr; }
  .two-col, .two-col.reverse { grid-template-columns: 1fr; direction: ltr; gap: 32px; }
  .merkle-features { grid-template-columns: repeat(2, 1fr); }
  .wedge-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }

  .cta-actions { flex-direction: column; }
}