@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Sans:wght@300;400;500;600;700&family=JetBrains+Mono:wght@400;500;600;700&display=swap');

/* ========== DESIGN TOKENS (from pro-max MASTER.md) ========== */
:root {
  --color-primary: #1E293B;
  --color-secondary: #334155;
  --color-cta: #22C55E;
  --color-cta-hover: #16A34A;
  --color-background: #0F172A;
  --color-surface: #1E293B;
  --color-surface-2: #334155;
  --color-border: #475569;
  --color-border-subtle: #334155;
  --color-text: #F8FAFC;
  --color-text-muted: #94A3B8;
  --color-text-dim: #7C8BA0;
  --color-code-bg: #0D1117;
  --color-inline-code: #E2E8F0;
  --color-link: #38BDF8;
  --color-link-hover: #7DD3FC;
  --color-warning: #F59E0B;
  --color-error: #EF4444;
  --color-info: #3B82F6;
  --color-ts: #3178C6;
  --color-py: #3776AB;
  --color-go: #00ADD8;
  --color-cs: #68217A;

  --font-heading: 'JetBrains Mono', monospace;
  --font-body: 'IBM Plex Sans', sans-serif;
  --font-code: 'JetBrains Mono', monospace;

  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.3);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.3);
  --shadow-xl: 0 20px 25px rgba(0,0,0,0.4);

  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;

  --transition: 200ms ease;
  --max-width: 1280px;
  --sidebar-width: 280px;
}

/* ========== RESET ========== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-body);
  background: var(--color-background);
  color: var(--color-text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
a { color: var(--color-link); text-decoration: none; transition: color var(--transition); cursor: pointer; }
a:hover { color: var(--color-link-hover); }
img { max-width: 100%; display: block; }

/* ========== LAYOUT ========== */
.page-wrapper {
  display: flex;
  min-height: 100vh;
}

/* Sidebar */
.sidebar {
  position: fixed;
  top: 0; left: 0;
  width: var(--sidebar-width);
  height: 100vh;
  background: var(--color-surface);
  border-right: 1px solid var(--color-border-subtle);
  overflow-y: auto;
  z-index: 100;
  padding: var(--space-lg) 0;
  transition: transform var(--transition);
}
.sidebar-header {
  padding: 0 var(--space-lg) var(--space-lg);
  border-bottom: 1px solid var(--color-border-subtle);
  margin-bottom: var(--space-md);
}
.sidebar-header h1 {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-cta);
  letter-spacing: -0.02em;
}
.sidebar-header .subtitle {
  font-size: 0.75rem;
  color: var(--color-text-dim);
  margin-top: var(--space-xs);
}
.sidebar-section {
  padding: var(--space-sm) var(--space-lg);
}
.sidebar-section-title {
  font-family: var(--font-heading);
  font-size: 0.65rem;
  font-weight: 600;
  color: var(--color-text-dim);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-sm);
}
.sidebar-link {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  color: var(--color-text-muted);
  transition: all var(--transition);
  cursor: pointer;
  margin-bottom: 2px;
}
.sidebar-link:hover {
  background: var(--color-surface-2);
  color: var(--color-text);
}
.sidebar-link.active {
  background: rgba(34, 197, 94, 0.1);
  color: var(--color-cta);
  font-weight: 500;
}
.sidebar-link .link-num {
  font-family: var(--font-heading);
  font-size: 0.7rem;
  color: var(--color-text-dim);
  min-width: 1.5rem;
}

/* Main content */
.main-content {
  margin-left: var(--sidebar-width);
  flex: 1;
  min-width: 0;
}
.content-area {
  max-width: 960px;
  margin: 0 auto;
  padding: var(--space-2xl) var(--space-xl);
}

/* Mobile sidebar toggle */
.sidebar-toggle {
  display: none;
  position: fixed;
  top: var(--space-md);
  left: var(--space-md);
  z-index: 200;
  background: var(--color-surface);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-md);
  padding: var(--space-sm) var(--space-md);
  color: var(--color-text);
  cursor: pointer;
  font-family: var(--font-heading);
  font-size: 0.85rem;
  transition: all var(--transition);
}
.sidebar-toggle:hover { background: var(--color-surface-2); }

@media (max-width: 768px) {
  .sidebar { transform: translateX(-100%); }
  .sidebar.open { transform: translateX(0); }
  .sidebar-toggle { display: block; }
  .main-content { margin-left: 0; }
  .content-area { padding: var(--space-xl) var(--space-md); padding-top: 4rem; }
}

/* ========== TYPOGRAPHY ========== */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.3;
}
h1 { font-size: 2rem; margin-bottom: var(--space-lg); color: var(--color-text); }
h2 {
  font-size: 1.5rem;
  margin-top: var(--space-3xl);
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-sm);
  border-bottom: 2px solid var(--color-cta);
  color: var(--color-text);
}
h3 {
  font-size: 1.15rem;
  margin-top: var(--space-2xl);
  margin-bottom: var(--space-md);
  color: var(--color-text);
}
h4 {
  font-size: 1rem;
  margin-top: var(--space-xl);
  margin-bottom: var(--space-sm);
  color: var(--color-text-muted);
}
p { margin-bottom: var(--space-md); color: var(--color-text-muted); }
strong { color: var(--color-text); font-weight: 600; }

/* Phase badge */
.phase-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  background: rgba(34, 197, 94, 0.1);
  border: 1px solid rgba(34, 197, 94, 0.3);
  border-radius: var(--radius-lg);
  padding: var(--space-sm) var(--space-lg);
  font-family: var(--font-heading);
  font-size: 0.8rem;
  color: var(--color-cta);
  margin-bottom: var(--space-xl);
}
.phase-badge .dot {
  width: 8px; height: 8px;
  background: var(--color-cta);
  border-radius: 50%;
  animation: pulse 2s infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

/* ========== TABLES ========== */
.table-wrapper {
  overflow-x: auto;
  margin: var(--space-lg) 0;
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border-subtle);
}
table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.875rem;
}
thead {
  background: var(--color-surface);
}
th {
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-dim);
  padding: var(--space-md) var(--space-lg);
  text-align: left;
  border-bottom: 2px solid var(--color-border-subtle);
}
td {
  padding: var(--space-md) var(--space-lg);
  border-bottom: 1px solid var(--color-border-subtle);
  color: var(--color-text-muted);
  vertical-align: top;
}
tr:last-child td { border-bottom: none; }
tr:hover td { background: rgba(255,255,255,0.02); }

/* ========== CODE BLOCKS ========== */
pre {
  background: var(--color-code-bg);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  overflow-x: auto;
  margin: var(--space-lg) 0;
  font-family: var(--font-code);
  font-size: 0.825rem;
  line-height: 1.6;
  color: var(--color-inline-code);
}
code {
  font-family: var(--font-code);
  font-size: 0.85em;
}
:not(pre) > code {
  background: rgba(255,255,255,0.06);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.15em 0.4em;
  color: var(--color-cta);
  font-size: 0.825em;
}

/* Language badge on code blocks */
pre[data-lang]::before {
  content: attr(data-lang);
  display: inline-block;
  position: relative;
  float: right;
  font-size: 0.65rem;
  font-family: var(--font-heading);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  background: var(--color-surface-2);
  color: var(--color-text-dim);
  margin: -8px -8px 0 0;
}

/* ========== CARDS / CALLOUTS ========== */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  margin: var(--space-lg) 0;
  transition: all var(--transition);
}
.card:hover {
  border-color: var(--color-border);
  box-shadow: var(--shadow-md);
}

.callout {
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  margin: var(--space-lg) 0;
  border-left: 4px solid;
}
.callout.info { background: rgba(59,130,246,0.08); border-color: var(--color-info); }
.callout.warning { background: rgba(245,158,11,0.08); border-color: var(--color-warning); }
.callout.success { background: rgba(34,197,94,0.08); border-color: var(--color-cta); }
.callout.error { background: rgba(239,68,68,0.08); border-color: var(--color-error); }
.callout-title {
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.875rem;
  margin-bottom: var(--space-sm);
}

/* ========== STATS GRID ========== */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: var(--space-md);
  margin: var(--space-lg) 0;
}
.stat-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  text-align: center;
  transition: all var(--transition);
}
.stat-card:hover {
  border-color: var(--color-cta);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}
.stat-value {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-cta);
  line-height: 1;
}
.stat-label {
  font-size: 0.8rem;
  color: var(--color-text-dim);
  margin-top: var(--space-sm);
}

/* ========== LANGUAGE PILLS ========== */
.lang-pills {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  margin: var(--space-md) 0;
}
.lang-pill {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-xs) var(--space-md);
  border-radius: 999px;
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 500;
  border: 1px solid;
}
.lang-pill.ts { background: rgba(49,120,198,0.1); border-color: rgba(49,120,198,0.3); color: var(--color-ts); }
.lang-pill.py { background: rgba(55,118,171,0.1); border-color: rgba(55,118,171,0.3); color: var(--color-py); }
.lang-pill.go { background: rgba(0,173,216,0.1); border-color: rgba(0,173,216,0.3); color: var(--color-go); }
.lang-pill.cs { background: rgba(104,33,122,0.1); border-color: rgba(104,33,122,0.3); color: var(--color-cs); }

/* ========== PROGRESS BAR ========== */
.progress-bar {
  height: 8px;
  background: var(--color-surface-2);
  border-radius: 4px;
  overflow: hidden;
  margin: var(--space-sm) 0;
}
.progress-fill {
  height: 100%;
  border-radius: 4px;
  transition: width 600ms ease;
}

/* ========== DIAGRAMS (CSS-only) ========== */
.diagram {
  background: var(--color-surface);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  margin: var(--space-xl) 0;
  overflow-x: auto;
}
.diagram-title {
  font-family: var(--font-heading);
  font-size: 0.8rem;
  color: var(--color-text-dim);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-lg);
  text-align: center;
}

/* Flow diagram */
.flow { display: flex; align-items: center; justify-content: center; flex-wrap: wrap; gap: var(--space-md); }
.flow-vertical { display: flex; flex-direction: column; align-items: center; gap: var(--space-md); }
.flow-node {
  padding: var(--space-md) var(--space-lg);
  border-radius: var(--radius-md);
  font-family: var(--font-heading);
  font-size: 0.825rem;
  font-weight: 500;
  text-align: center;
  min-width: 120px;
  border: 1px solid;
  transition: all var(--transition);
}
.flow-node:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }
.flow-node.primary { background: rgba(34,197,94,0.12); border-color: var(--color-cta); color: var(--color-cta); }
.flow-node.secondary { background: rgba(59,130,246,0.1); border-color: var(--color-info); color: var(--color-link); }
.flow-node.tertiary { background: rgba(148,163,184,0.1); border-color: var(--color-text-dim); color: var(--color-text-muted); }
.flow-node.accent { background: rgba(245,158,11,0.1); border-color: var(--color-warning); color: var(--color-warning); }
.flow-node.ts-node { background: rgba(49,120,198,0.1); border-color: var(--color-ts); color: var(--color-ts); }
.flow-node.py-node { background: rgba(55,118,171,0.1); border-color: var(--color-py); color: var(--color-py); }
.flow-node.go-node { background: rgba(0,173,216,0.1); border-color: var(--color-go); color: var(--color-go); }
.flow-node.cs-node { background: rgba(104,33,122,0.1); border-color: var(--color-cs); color: var(--color-cs); }

.flow-arrow {
  color: var(--color-text-dim);
  font-size: 1.2rem;
  flex-shrink: 0;
}
.flow-arrow-down {
  color: var(--color-text-dim);
  font-size: 1.2rem;
  text-align: center;
}

/* Box diagram (layered architecture) */
.layer-stack {
  display: flex;
  flex-direction: column;
  gap: 2px;
  max-width: 600px;
  margin: 0 auto;
}
.layer {
  padding: var(--space-md) var(--space-lg);
  text-align: center;
  font-family: var(--font-heading);
  font-size: 0.825rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
  border: 1px solid;
  transition: all var(--transition);
}
.layer:hover { transform: scale(1.01); box-shadow: var(--shadow-md); }
.layer-label {
  font-size: 0.65rem;
  color: var(--color-text-dim);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  display: block;
  margin-bottom: 2px;
}
.layer.l1 { background: rgba(34,197,94,0.12); border-color: rgba(34,197,94,0.3); color: var(--color-cta); }
.layer.l2 { background: rgba(59,130,246,0.1); border-color: rgba(59,130,246,0.3); color: var(--color-link); }
.layer.l3 { background: rgba(245,158,11,0.1); border-color: rgba(245,158,11,0.3); color: var(--color-warning); }
.layer.l4 { background: rgba(148,163,184,0.1); border-color: rgba(148,163,184,0.3); color: var(--color-text-muted); }
.layer.l5 { background: rgba(239,68,68,0.08); border-color: rgba(239,68,68,0.3); color: var(--color-error); }

/* Grid diagram (mirror pattern, dep graph) */
.sdk-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-md);
}
@media (max-width: 768px) { .sdk-grid { grid-template-columns: repeat(2, 1fr); } }
.sdk-col {
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.sdk-col-header {
  padding: var(--space-md);
  text-align: center;
  font-family: var(--font-heading);
  font-size: 0.825rem;
  font-weight: 600;
}
.sdk-col-header.ts { background: rgba(49,120,198,0.15); color: var(--color-ts); }
.sdk-col-header.py { background: rgba(55,118,171,0.15); color: var(--color-py); }
.sdk-col-header.go { background: rgba(0,173,216,0.15); color: var(--color-go); }
.sdk-col-header.cs { background: rgba(104,33,122,0.15); color: var(--color-cs); }
.sdk-col-item {
  padding: var(--space-sm) var(--space-md);
  border-bottom: 1px solid var(--color-border-subtle);
  font-size: 0.8rem;
  color: var(--color-text-muted);
  font-family: var(--font-code);
}
.sdk-col-item:last-child { border-bottom: none; }

/* Sequence diagram */
.sequence {
  font-family: var(--font-code);
  font-size: 0.8rem;
  position: relative;
}
.seq-participants {
  display: flex;
  justify-content: space-between;
  margin-bottom: var(--space-lg);
}
.seq-participant {
  padding: var(--space-sm) var(--space-lg);
  border-radius: var(--radius-md);
  font-weight: 600;
  text-align: center;
  min-width: 140px;
}
.seq-row {
  display: flex;
  align-items: center;
  margin: var(--space-sm) 0;
  position: relative;
}
.seq-arrow {
  flex: 1;
  height: 2px;
  background: var(--color-border);
  position: relative;
  margin: 0 var(--space-md);
}
.seq-arrow::after {
  content: '';
  position: absolute;
  right: -1px; top: -4px;
  border: 5px solid transparent;
  border-left: 6px solid var(--color-border);
}
.seq-arrow.reverse::after {
  right: auto; left: -1px;
  border-left: none;
  border-right: 6px solid var(--color-border);
}
.seq-label {
  position: absolute;
  top: -18px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 0.7rem;
  color: var(--color-text-dim);
  white-space: nowrap;
  background: var(--color-surface);
  padding: 0 var(--space-sm);
}

/* Dep graph (tree) */
.dep-tree {
  padding-left: var(--space-xl);
}
.dep-tree-item {
  position: relative;
  padding: var(--space-sm) 0 var(--space-sm) var(--space-lg);
  margin-left: var(--space-md);
  border-left: 2px solid var(--color-border-subtle);
}
.dep-tree-item::before {
  content: '';
  position: absolute;
  left: -2px; top: 50%;
  width: var(--space-md);
  height: 2px;
  background: var(--color-border-subtle);
}
.dep-tree-label {
  font-family: var(--font-code);
  font-size: 0.8rem;
  color: var(--color-text-muted);
}

/* ========== TAB SYSTEM (for multi-language code) ========== */
.code-tabs {
  margin: var(--space-lg) 0;
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.tab-bar {
  display: flex;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border-subtle);
}
.tab-btn {
  padding: var(--space-sm) var(--space-lg);
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--color-text-dim);
  background: none;
  border: none;
  cursor: pointer;
  transition: all var(--transition);
  border-bottom: 2px solid transparent;
}
.tab-btn:hover { color: var(--color-text); background: rgba(255,255,255,0.03); }
.tab-btn.active { color: var(--color-cta); border-bottom-color: var(--color-cta); }
.tab-panel { display: none; }
.tab-panel.active { display: block; }
.tab-panel pre { margin: 0; border: none; border-radius: 0; }

/* ========== LISTS ========== */
ul, ol {
  margin: var(--space-md) 0 var(--space-md) var(--space-xl);
  color: var(--color-text-muted);
}
li { margin-bottom: var(--space-xs); }
li::marker { color: var(--color-text-dim); }

/* ========== SCROLL TO TOP ========== */
.scroll-top {
  position: fixed;
  bottom: var(--space-xl);
  right: var(--space-xl);
  width: 44px; height: 44px;
  background: var(--color-surface);
  border: 1px solid var(--color-border-subtle);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-muted);
  cursor: pointer;
  transition: all var(--transition);
  opacity: 0;
  pointer-events: none;
  z-index: 50;
}
.scroll-top.visible { opacity: 1; pointer-events: auto; }
.scroll-top:hover { background: var(--color-cta); color: white; border-color: var(--color-cta); }

/* ========== TOC (in-page) ========== */
.toc {
  background: var(--color-surface);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  margin: var(--space-xl) 0;
}
.toc-title {
  font-family: var(--font-heading);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-text-dim);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-md);
}
.toc-list { list-style: none; margin: 0; padding: 0; }
.toc-list li { margin-bottom: var(--space-xs); }
.toc-list a {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}
.toc-list a:hover { background: var(--color-surface-2); color: var(--color-text); }
.toc-num {
  font-family: var(--font-heading);
  font-size: 0.7rem;
  color: var(--color-text-dim);
  min-width: 1.5rem;
}

/* ========== FILE REFERENCE ========== */
.file-ref {
  font-family: var(--font-code);
  font-size: 0.8rem;
  color: var(--color-link);
  background: rgba(56,189,248,0.06);
  padding: 1px 6px;
  border-radius: var(--radius-sm);
}

/* ========== GRID LAYOUTS ========== */
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-md); }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-md); }
@media (max-width: 768px) {
  .grid-2, .grid-3 { grid-template-columns: 1fr; }
}

/* ========== PRINT ========== */
@media print {
  .sidebar, .sidebar-toggle, .scroll-top { display: none !important; }
  .main-content { margin-left: 0; }
  body { background: white; color: #111; }
  .card, .stat-card, .diagram { border: 1px solid #ddd; }
}

/* ========== MERMAID DIAGRAMS ========== */
.mermaid-wrapper {
  background: var(--color-surface);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  margin: var(--space-xl) 0;
  overflow-x: auto;
}
.mermaid-wrapper .diagram-title {
  font-family: var(--font-heading);
  font-size: 0.8rem;
  color: var(--color-text-dim);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-lg);
  text-align: center;
}
.mermaid-wrapper .mermaid {
  display: flex;
  justify-content: center;
}
.mermaid-wrapper .mermaid svg {
  max-width: 100%;
  height: auto;
}

/* ========== HIGHLIGHT.JS OVERRIDES ========== */
.hljs {
  background: transparent !important;
  padding: 0 !important;
}
pre code.hljs {
  background: transparent !important;
}

/* ========== PREV/NEXT PAGE NAVIGATION ========== */
.page-nav {
  display: flex;
  justify-content: space-between;
  gap: var(--space-lg);
  margin-top: var(--space-3xl);
  padding-top: var(--space-xl);
  border-top: 1px solid var(--color-border-subtle);
}
.page-nav-link {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
  padding: var(--space-md) var(--space-lg);
  background: var(--color-surface);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-lg);
  transition: all var(--transition);
  max-width: 45%;
  text-decoration: none;
}
.page-nav-link:hover {
  border-color: var(--color-cta);
  box-shadow: var(--shadow-md);
}
.page-nav-link.next { margin-left: auto; text-align: right; }
.page-nav-label {
  font-family: var(--font-heading);
  font-size: 0.7rem;
  color: var(--color-text-dim);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}
.page-nav-title {
  font-size: 0.9rem;
  color: var(--color-cta);
  font-weight: 500;
}

/* ========== SECTION DIVIDERS ========== */
.content-area section + section {
  margin-top: var(--space-3xl);
  padding-top: var(--space-2xl);
  border-top: 1px solid var(--color-border-subtle);
}

/* ========== SCROLL ANCHORS ========== */
h2[id], h3[id], h4[id] {
  scroll-margin-top: 4rem;
}