/* ── Project page nav elements ── */
.nav-spacer { flex: 1; }
.nav-brand { font-weight: 700; color: var(--text); font-size: var(--text-base); }
.nav-brand:hover { text-decoration: none; color: var(--accent); }
.nav-back {
  flex: 1;
  display: flex; align-items: center; gap: 0.375rem;
  color: var(--muted); font-size: var(--text-sm); font-weight: 500;
  min-height: 44px; padding: 0 var(--sp-1);
}
.nav-back:hover { color: var(--accent); text-decoration: none; }

/* ── PAGE HERO ── */
.page-hero {
  max-width: 900px; margin: 0 auto;
  padding: calc(60px + var(--sp-6)) var(--sp-4) var(--sp-6);
  text-align: center;
}
.page-hero-icon { font-size: 1em; line-height: 1; }
.page-hero h1 {
  display: flex; align-items: center; justify-content: center; gap: 0.4em;
  font-size: clamp(2rem, 5vw, 3rem); font-weight: 800;
  letter-spacing: -0.02em; line-height: 1.15; margin-bottom: var(--sp-2);
}
.page-hero p {
  font-size: var(--text-lg); color: var(--muted);
  line-height: 1.75; margin-bottom: var(--sp-3);
}
.page-hero .proj-tags { justify-content: center; }
.page-hero .hero-btns { justify-content: center; margin-top: var(--sp-3); margin-bottom: var(--sp-4); }

/* ── CONTENT SECTION ── */
.content-section {
  max-width: 900px; margin: 0 auto;
  padding: var(--sp-8) var(--sp-4);
  border-top: 1px solid var(--border);
}
.content-section h2 {
  font-size: clamp(1.4rem, 3vw, 1.75rem); font-weight: 700;
  letter-spacing: -0.02em; margin-bottom: var(--sp-3);
  margin-top: var(--sp-1);
}
.content-section > p {
  color: var(--muted); line-height: 1.75;
  margin-bottom: var(--sp-3);
}
.content-section .section-label {
  color: var(--accent);
  margin-bottom: var(--sp-1);
  line-height: 1.4;
}

/* ── ALGO GRID ── */
.algo-grid { display: grid; grid-template-columns: 1fr 1fr; gap: var(--sp-3); margin-top: var(--sp-3); }
.algo-grid--single { grid-template-columns: 1fr; }
.algo-card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: var(--sp-4);
}
.algo-card .algo-icon { font-size: 1.75rem; margin-bottom: var(--sp-2); }
.algo-card h3 { font-size: var(--text-base); font-weight: 700; margin-bottom: var(--sp-2); }
.algo-card > p { font-size: var(--text-sm); color: var(--muted); line-height: 1.7; margin-bottom: var(--sp-2); }
.algo-card ul { list-style: none; padding: 0; display: flex; flex-direction: column; gap: 0.375rem; }
.algo-card ul li {
  font-size: var(--text-sm); color: var(--muted);
  display: flex; gap: 0.5rem; align-items: flex-start;
}
.algo-card ul li::before { content: '→'; color: var(--accent); font-weight: 600; flex-shrink: 0; }

/* ── HIGHLIGHT GRID ── */
.highlight-grid {
  display: grid; grid-template-columns: repeat(2, 1fr);
  gap: var(--sp-3); margin-top: var(--sp-3); align-items: start;
}
.decision-list {
  display: flex; flex-direction: column;
  gap: var(--sp-3); margin-top: var(--sp-3);
}
.highlight-card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: var(--sp-3);
}
.highlight-card h3 { font-size: var(--text-base); font-weight: 600; margin-bottom: 0.625rem; }
.highlight-card p { font-size: var(--text-sm); color: var(--muted); line-height: 1.65; }
.highlight-card ul {
  list-style: none; padding: 0;
  margin-top: 0.5rem;
  display: flex; flex-direction: column; gap: 0.375rem;
}
.highlight-card ul li {
  font-size: var(--text-sm); color: var(--muted);
  position: relative; padding-left: 1.25rem; line-height: 1.6;
}
.highlight-card ul li::before { content: '→'; color: var(--accent); font-weight: 600; position: absolute; left: 0; top: 0; }
.highlight-card ul li strong { white-space: nowrap; }

/* ── CTA SECTION ── */
.cta-section {
  max-width: 900px; margin: 0 auto;
  padding: var(--sp-8) var(--sp-4);
  border-top: 1px solid var(--border);
  display: flex; align-items: center;
  justify-content: space-between; gap: var(--sp-4); flex-wrap: wrap;
}
.cta-section h2 { font-size: var(--text-xl); font-weight: 700; margin-bottom: 0.25rem; }
.cta-section p { color: var(--muted); font-size: var(--text-sm); }
.cta-links { display: flex; gap: var(--sp-2); flex-wrap: wrap; align-items: center; }

/* ── ARCHITECTURE IMAGE ── */
.arch-img {
  width: 100%; height: auto; display: block;
  border-radius: var(--radius-lg); border: 1px solid var(--border);
  margin-top: var(--sp-3);
}

.btn-icon { margin-right: 8px; }

/* ── DETAIL LISTS ── */
.content-section ul.detail-list {
  list-style: none; padding: 0;
  margin: var(--sp-2) 0 var(--sp-3);
  display: flex; flex-direction: column; gap: 0.5rem;
}
.content-section ul.detail-list li {
  font-size: var(--text-sm); color: var(--muted);
  display: flex; gap: 0.5rem; align-items: flex-start; line-height: 1.65;
}
.content-section ul.detail-list li::before {
  content: '→'; color: var(--accent); font-weight: 600; flex-shrink: 0;
}

/* ── FAILURE MODES TABLE ── */
.failure-table {
  width: 100%; border-collapse: collapse;
  margin-top: var(--sp-3); font-size: var(--text-sm);
}
.failure-table th {
  text-align: left; font-size: var(--text-xs); font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.08em;
  color: var(--muted); padding: var(--sp-1) var(--sp-2);
  border-bottom: 2px solid var(--border);
}
.failure-table td {
  padding: 0.75rem var(--sp-2); border-bottom: 1px solid var(--border);
  color: var(--muted); line-height: 1.55; vertical-align: top;
}
.failure-table td:first-child { font-weight: 600; color: var(--text-secondary); width: 34%; }
.failure-table tr:last-child td { border-bottom: none; }

/* ── TLDR ── */
.tldr-section {
  max-width: 900px; margin: 0 auto;
  padding: var(--sp-4) var(--sp-4) var(--sp-4);
  border-top: 1px solid var(--border);
}
.tldr-section h2 {
  font-size: var(--text-sm); font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.08em;
  color: var(--accent); margin-bottom: var(--sp-2);
}
.tldr-section ul {
  list-style: none; padding: 0;
  display: flex; flex-direction: column; gap: 0.5rem;
}
.tldr-section ul li {
  font-size: var(--text-base); color: var(--text-secondary);
  display: flex; gap: 0.5rem; align-items: flex-start; line-height: 1.6;
}
.tldr-section ul li::before { content: '→'; color: var(--accent); font-weight: 700; flex-shrink: 0; }
.tldr-section ul li span { flex: 1; min-width: 0; }

/* ── PAGE LAYOUT (sidebar + content) ── */
.page-layout {
  max-width: 1020px; margin: 0 auto;
  padding: 0 var(--sp-4) 0;
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: var(--sp-6);
  align-items: start;
}

.page-sidebar {
  position: sticky;
  top: calc(60px + var(--sp-4));
}


/* ── TOC NAV (sticky sidebar) ── */
.toc-nav {
  display: flex;
  flex-direction: column;
  gap: 0;
  padding: 0;
  border-left: 2px solid var(--border);
  padding-left: var(--sp-3);
}
.toc-nav a {
  font-size: 0.8125rem; font-weight: 500;
  color: var(--muted); text-decoration: none;
  padding: 0.45rem 0;
  display: block; line-height: 1.4;
  transition: color 0.15s;
}
.toc-nav a:hover { color: var(--accent); text-decoration: none; }
.toc-nav a.active { color: var(--accent); font-weight: 600; }

/* ── COLLAPSIBLE THRESHOLDS ── */
details.thresholds { margin-top: 0.75rem; }
details.thresholds > summary {
  font-size: var(--text-xs); font-weight: 600;
  color: var(--accent); cursor: pointer; list-style: none;
  user-select: none; display: flex; align-items: center; gap: 0.375rem;
}
details.thresholds > summary::-webkit-details-marker { display: none; }
details.thresholds > summary::before { content: '▸'; display: inline-block; transition: transform 0.2s; }
details[open].thresholds > summary::before { transform: rotate(90deg); }
.threshold-body {
  margin-top: 0.5rem; padding: 0.5rem 0.75rem;
  background: var(--bg); border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}
.threshold-body li {
  font-size: var(--text-xs); color: var(--muted); line-height: 1.7;
  display: flex; gap: 0.375rem; align-items: flex-start; padding: 0.1rem 0;
}
.algo-card .threshold-body li::before { content: '–'; color: var(--muted); font-weight: 400; }

/* ── PHASE BLOCKS (orchestrator) ── */
.phase-block {
  margin-top: 0.625rem; padding: 0.5rem 0.75rem;
  border-left: 3px solid var(--accent);
  background: var(--bg); border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}
.phase-block h4 {
  font-size: var(--text-xs); font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.07em;
  color: var(--accent); margin-bottom: 0.4rem;
}
.algo-card .phase-block ul { gap: 0.2rem; margin-top: 0; }
.algo-card .phase-block ul li { font-size: var(--text-xs); }
.algo-card .phase-block ul li::before { content: '–'; color: var(--muted); font-weight: 400; }

/* ── INCIDENT WALKTHROUGH ── */
.incident-grid {
  display: grid; grid-template-columns: 1fr 1fr;
  gap: var(--sp-3); margin-top: var(--sp-3);
}
.incident-panel {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: var(--sp-2) var(--sp-3);
}
.incident-panel h4 {
  font-size: var(--text-xs); font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.07em;
  color: var(--muted); margin-bottom: var(--sp-1);
}
.incident-verdict {
  margin-top: var(--sp-3); padding: var(--sp-2) var(--sp-3);
  background: var(--surface); border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: 0 var(--radius) var(--radius) 0;
}
.incident-verdict h4 {
  font-size: var(--text-xs); font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.07em;
  color: var(--accent); margin-bottom: 0.5rem;
}
.incident-verdict p {
  font-size: var(--text-sm); color: var(--muted);
  line-height: 1.65; margin-bottom: 0.375rem;
}
.incident-verdict p:last-child { margin-bottom: 0; }

/* ── TABLE OVERFLOW WRAPPER ── */
.table-wrapper { overflow-x: auto; -webkit-overflow-scrolling: touch; }

/* ── SCREEN READER ONLY ── */
.sr-only {
  position: absolute; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0,0,0,0); white-space: nowrap; border-width: 0;
}

/* ── SECTION-LEVEL EXPAND ── */
details.section-expand { margin-top: var(--sp-3); }
details.section-expand > summary {
  display: inline-flex; align-items: center; gap: 0.4rem;
  font-size: var(--text-xs); font-weight: 600;
  color: var(--muted); cursor: pointer; list-style: none; user-select: none;
  padding: 0.3rem 0.75rem;
  border: 1px solid var(--border); border-radius: 999px;
  background: var(--surface);
  transition: color 0.15s, border-color 0.15s;
}
details.section-expand > summary::-webkit-details-marker { display: none; }
details.section-expand > summary::before {
  content: '▸'; display: inline-block; transition: transform 0.2s; font-size: 0.65rem;
}
details[open].section-expand > summary::before { transform: rotate(90deg); }
details.section-expand > summary:hover { color: var(--accent); border-color: var(--accent); }
details.section-expand > .section-expand-body { margin-top: var(--sp-3); }
.section-expand-body > p {
  font-size: var(--text-sm); color: var(--muted);
  line-height: 1.75; margin-bottom: var(--sp-2);
}
.section-expand-body > p:last-child { margin-bottom: 0; }

/* ── CORE INNOVATION CARDS ── */
.highlight-card--core { border-left: 3px solid var(--accent); }
.core-badge {
  display: inline-flex; align-items: center; gap: 0.2rem;
  font-size: 0.625rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.09em;
  color: var(--accent); border: 1px solid var(--accent);
  border-radius: 999px; padding: 0.1rem 0.45rem;
  margin-bottom: 0.4rem;
}

/* ── PERFORMANCE METRICS ── */
.perf-metrics {
  display: grid; grid-template-columns: repeat(12, 1fr);
  gap: var(--sp-2); margin: var(--sp-3) 0;
  padding: var(--sp-3); background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius);
}
.perf-metric { text-align: center; padding: var(--sp-1) 0; }
.perf-metric:nth-child(-n+4) { grid-column: span 3; }
.perf-metric:nth-child(n+5)  { grid-column: span 4; }
.perf-metric-value {
  font-size: clamp(1rem, 2.5vw, 1.25rem); font-weight: 700;
  font-variant-numeric: tabular-nums; color: var(--accent);
  line-height: 1.2; display: block;
}
.perf-metric-label {
  font-size: var(--text-xs); color: var(--muted);
  line-height: 1.4; display: block; margin-top: 0.3rem;
}

/* ── THRESHOLD TABLE (mini, inside agent cards) ── */
.threshold-table {
  width: 100%; border-collapse: collapse;
  margin-top: 0.375rem; font-size: var(--text-xs);
}
.threshold-table th {
  text-align: left; font-weight: 600;
  color: var(--muted); padding: 0.15rem 0.375rem 0.3rem;
  border-bottom: 1px solid var(--border);
}
.threshold-table td {
  padding: 0.2rem 0.375rem; color: var(--muted); line-height: 1.4;
}
.threshold-table td:first-child {
  font-weight: 600; color: var(--text-secondary); white-space: nowrap;
}

/* ── HERO METRICS STRIP ── */
.hero-metrics {
  display: flex; justify-content: center; flex-wrap: wrap; gap: var(--sp-2);
  margin-top: var(--sp-4);
}
.hero-metrics div {
  font-size: var(--text-sm); font-weight: 600;
  color: var(--text-secondary);
  background: var(--surface); border: 1px solid var(--border);
  border-radius: 999px; padding: 0.3rem 0.875rem;
  white-space: nowrap;
}

/* ── MOTIVATION SECTION ── */
.motivation-section {
  max-width: 900px; margin: 0 auto;
  padding: var(--sp-3) var(--sp-4) var(--sp-5);
  border-top: 1px solid var(--border);
}
.motivation-section p {
  font-size: var(--text-base); color: var(--muted); line-height: 1.75;
}

/* ── CODE BLOCKS (LLM output examples) ── */
.llm-output-grid {
  display: grid; grid-template-columns: 1fr 1fr;
  gap: var(--sp-3); margin-top: var(--sp-2);
}
.llm-output-label {
  font-size: var(--text-xs); font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.07em;
  color: var(--muted); margin-bottom: 0.5rem;
}
.code-block-wrapper {
  border-radius: var(--radius-sm); overflow: hidden;
  border: 1px solid var(--border);
}

/* ── COLLAPSIBLE CODE BLOCKS ── */
.code-collapsible {
  border-radius: var(--radius-sm); overflow: hidden;
  border: 1px solid var(--border);
}
.code-collapsible > summary {
  cursor: pointer; list-style: none; user-select: none;
}
.code-collapsible > summary::-webkit-details-marker { display: none; }
.code-collapsible > summary:hover { background: var(--bg); }
.collapse-chevron {
  display: inline-block; font-size: 0.6rem; margin-right: 0.35rem;
  color: var(--muted); transition: transform 0.2s; vertical-align: middle;
}
details[open].code-collapsible > summary .collapse-chevron { transform: rotate(90deg); }
.code-block-header {
  display: flex; align-items: center; justify-content: space-between;
  background: var(--surface); padding: 0.45rem 1rem;
  border-bottom: 1px solid var(--border);
}
.code-block-label {
  font-size: 0.65rem; color: var(--muted);
  font-family: 'SF Mono', 'Fira Code', monospace;
  text-transform: uppercase; letter-spacing: 0.06em; font-weight: 600;
}
.copy-btn {
  display: flex; align-items: center; gap: 0.3rem;
  font-size: 0.65rem; color: var(--muted); background: var(--bg);
  border: 1px solid var(--border); border-radius: var(--radius-sm);
  padding: 0.18rem 0.55rem; cursor: pointer; font-family: inherit;
  transition: color 0.15s, border-color 0.15s;
}
.copy-btn:hover { color: var(--text); border-color: var(--muted); }
.copy-btn.copied { color: #16a34a; border-color: #16a34a; }
.code-tabs { display: flex; gap: 0.25rem; align-items: center; }
.code-tab {
  font-size: 0.65rem; padding: 0.22rem 0.6rem;
  background: transparent; border: 1px solid transparent;
  border-radius: 4px; cursor: pointer; color: var(--muted);
  font-family: inherit; transition: all 0.15s;
}
.code-tab.active { background: var(--bg); color: var(--text); border-color: var(--border); font-weight: 600; }
.code-tab-panel { display: none; }
.code-tab-panel.active { display: block; }
.http-proto { color: var(--muted); }
.http-status-ok { color: #1a7f37; font-weight: 600; }
.http-status-err { color: #cf222e; font-weight: 600; }
.http-header-name { color: #0550ae; }
.http-header-val { color: var(--text-secondary); }
.field-notes { font-size: 0.68rem; color: var(--muted); padding-top: 0.6rem; line-height: 1.7; }
.badge-required {
  display: inline-block; padding: 0.08rem 0.4rem;
  background: #dcfce7; color: #15803d; border-radius: 3px;
  font-size: 0.6rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em;
}
.badge-optional {
  display: inline-block; padding: 0.08rem 0.4rem;
  background: var(--surface); color: var(--muted); border: 1px solid var(--border);
  border-radius: 3px; font-size: 0.6rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em;
}
pre.code-block {
  background: var(--bg); padding: 1rem 1.1rem;
  overflow-x: auto; margin: 0; border: none; border-radius: 0;
}
pre.code-block code {
  font-family: 'SF Mono', 'Fira Code', 'Fira Mono', 'Roboto Mono', monospace;
  font-size: 0.75rem; line-height: 1.7;
  color: var(--text-secondary); white-space: pre; word-break: normal;
}
.json-key   { color: #0550ae; }
.json-str   { color: #0a3069; }
.json-num   { color: #0550ae; }
.json-bool  { color: #cf222e; }
.http-method { color: #1a7f37; font-weight: 600; }
.http-path   { color: var(--text-secondary); }

/* ── STATS GRID ── */
.stats-grid {
  display: grid; grid-template-columns: repeat(3, 1fr);
  gap: var(--sp-3); margin-top: var(--sp-3);
}
.stat-card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: var(--sp-4) var(--sp-3);
  text-align: center;
}
.stat-number {
  font-size: clamp(1.6rem, 3.5vw, 2.25rem); font-weight: 800;
  letter-spacing: -0.03em; color: var(--accent); line-height: 1.1;
  margin-bottom: 0.375rem;
}
.stat-label {
  font-size: var(--text-sm); color: var(--muted); line-height: 1.4;
}

/* ── REDUCED MOTION ── */
@media (prefers-reduced-motion: reduce) {
  details.thresholds > summary::before { transition: none; }
  details.section-expand > summary::before { transition: none; }
  .collapse-chevron { transition: none; }
}

/* ── MOBILE ── */
@media (max-width: 680px) {
  .algo-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: 1fr; }
  .cta-section { flex-direction: column; align-items: flex-start; }
  .cta-links { flex-direction: column; }
  .cta-links .btn { width: 100%; justify-content: center; }
  .incident-grid { grid-template-columns: 1fr; }
  .failure-table { font-size: var(--text-xs); }
  .failure-table td:first-child { width: auto; min-width: 110px; }
  .llm-output-grid { grid-template-columns: 1fr; }

  /* Collapse sidebar into horizontal pill row on mobile (layout reserved for future use) */
  .page-layout {
    grid-template-columns: 1fr;
    gap: 0;
    padding: 0;
  }
  .page-sidebar { position: static; }
  .toc-nav {
    flex-direction: row; flex-wrap: wrap; gap: 0.375rem;
    border-left: none; padding-left: 0;
    padding: var(--sp-3) var(--sp-4);
    border-bottom: 1px solid var(--border);
  }
  .toc-nav a {
    border: 1px solid var(--border); border-radius: 999px;
    padding: 0.2rem 0.6rem;
  }
  .toc-nav a:hover { border-color: var(--accent); }
}