/* ── Placeholder content ─────────────────────────────────── */
.placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100%;
  padding: 48px;
  text-align: center;
  gap: 16px;
}

.placeholder-label {
  font-family: "DM Mono", monospace;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--gold);
}

.placeholder-title {
  font-family: "DM Serif Display", serif;
  font-size: 36px;
  line-height: 1.1;
}

#cover .placeholder-title {
  color: var(--cover-text);
}
.interior .placeholder-title {
  color: var(--interior-text);
}

.placeholder-body {
  font-family: "Lora", serif;
  font-size: 15px;
  line-height: 1.7;
  max-width: 520px;
}

#cover .placeholder-body {
  color: #7a7672;
}
.interior .placeholder-body {
  color: var(--ink-muted);
}

/* ── Table of Contents ───────────────────────────────────── */
.toc-inner {
  max-width: 66.667%;
  padding: 48px 48px 64px 40px;
}

.toc-header {
  margin-bottom: 56px;
  padding-bottom: 24px;
  border-bottom: 0.5px solid var(--gold-divider);
}

.page-eyebrow {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 12px;
}

.page-title {
  font-family: "DM Serif Display", serif;
  font-size: 40px;
  line-height: 1.05;
  color: var(--interior-text);
  letter-spacing: -0.01em;
}

.toc-list {
  list-style: none;
  display: flex;
  flex-direction: column;
}

.toc-entry {
  display: flex;
  align-items: baseline;
  gap: 20px;
  padding: 22px 0;
  border-bottom: 0.5px solid var(--border-light);
  cursor: pointer;
  transition: opacity 0.15s;
}

.toc-entry:last-child {
  border-bottom: none;
}

.toc-entry:hover .toc-chapter-title {
  color: var(--gold-dark);
}

.toc-entry:hover .toc-num {
  color: var(--gold-dark);
}

.toc-num {
  font-family: "DM Mono", monospace;
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--gold);
  text-transform: uppercase;
  min-width: 28px;
  flex-shrink: 0;
  padding-top: 6px;
  transition: color 0.15s;
}

.toc-body {
  display: flex;
  align-items: baseline;
  flex: 1;
  gap: 0;
  min-width: 0;
}

.toc-chapter-title {
  font-family: "DM Serif Display", serif;
  font-size: 24px;
  line-height: 1.15;
  color: var(--interior-text);
  white-space: nowrap;
  transition: color 0.15s;
}

.toc-leaders {
  flex: 1;
  margin: 0 14px;
  border-bottom: 1px dotted #c8bfb0;
  position: relative;
  top: -4px;
  min-width: 24px;
}

.toc-tag {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-faint);
  white-space: nowrap;
  flex-shrink: 0;
}

/* ── Interior chapter layout ─────────────────────────────── */
.ch-inner {
  max-width: 66.667%;
  padding: 48px 48px 80px 40px;
}

.ch-header {
  margin-bottom: 48px;
  padding-bottom: 28px;
  border-bottom: 0.5px solid var(--gold-divider);
}

.ch-eyebrow {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 14px;
}

.ch-title {
  font-family: "DM Serif Display", serif;
  font-size: 42px;
  line-height: 1.05;
  color: var(--interior-text);
  letter-spacing: -0.01em;
}

/* Body prose */
.ch-body {
  font-family: "Lora", serif;
  font-size: 16px;
  line-height: 1.85;
  color: var(--interior-text);
}

.ch-body p + p {
  margin-top: 24px;
}

/* Drop cap */
.drop-cap::first-letter {
  font-family: "DM Serif Display", serif;
  font-size: 4.8em;
  line-height: 0.72;
  float: left;
  margin: 0.06em 0.1em 0 0;
  color: var(--gold-dark);
}

/* Pull quote */
.pull-quote {
  margin: 44px 0;
  padding: 4px 0 4px 28px;
  border-left: 2.5px solid var(--gold-dark);
}

.pull-quote p {
  font-family: "Lora", serif;
  font-style: italic;
  font-size: 20px;
  line-height: 1.55;
  color: var(--interior-text);
}

/* Aside block */
.aside {
  margin: 40px 0;
  padding: 20px 24px;
  border-left: 2px solid var(--gold);
  background: rgba(196, 154, 60, 0.05);
}

.aside-label {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 10px;
}

.aside p {
  font-family: "Lora", serif;
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-muted);
}

/* Stat row */
.stat-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border: 0.5px solid var(--border-light);
  border-radius: 3px;
  overflow: hidden;
  margin: 44px 0;
}

.stat-row-cell {
  padding: 20px 20px 16px;
  border-right: 0.5px solid var(--border-light);
}

.stat-row-cell:last-child {
  border-right: none;
}

.stat-row-num {
  font-family: "DM Serif Display", serif;
  font-size: 26px;
  color: var(--interior-text);
  line-height: 1;
  margin-bottom: 6px;
}

.stat-row-label {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-faint);
}

/* ── Agent section (Ch III) ──────────────────────────────── */
.agent-section {
  margin-top: 48px;
  padding-top: 40px;
  border-top: 0.5px solid var(--gold-divider);
}

.agent-section:first-of-type {
  margin-top: 36px;
}

.agent-header {
  display: flex;
  align-items: baseline;
  gap: 16px;
  margin-bottom: 20px;
}

.agent-name {
  font-family: "DM Serif Display", serif;
  font-size: 32px;
  color: var(--interior-text);
  line-height: 1;
}

.agent-tag {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--gold);
  padding: 3px 8px;
  border: 0.5px solid var(--gold);
  border-radius: 2px;
}

/* Technical detail list */
.tech-list {
  list-style: none;
  margin-top: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.tech-list li {
  font-family: "Lora", serif;
  font-size: 14px;
  line-height: 1.65;
  color: var(--ink-muted);
  padding-left: 20px;
  position: relative;
}

.tech-list li::before {
  content: "→";
  position: absolute;
  left: 0;
  color: var(--gold-dark);
  font-family: "DM Mono", monospace;
  font-size: 11px;
}

.tech-list code {
  font-family: "DM Mono", monospace;
  font-size: 12px;
  background: rgba(154, 111, 42, 0.08);
  color: var(--gold-dark);
  padding: 1px 5px;
  border-radius: 2px;
}

/* Inline code in prose */
.ch-body code {
  font-family: "DM Mono", monospace;
  font-size: 13px;
  background: rgba(154, 111, 42, 0.08);
  color: var(--gold-dark);
  padding: 1px 5px;
  border-radius: 2px;
}

/* Outcome section */
.outcome-section {
  margin-top: 52px;
  padding-top: 36px;
  border-top: 0.5px solid var(--gold-divider);
}

.outcome-label {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 16px;
}

/* ── Code block (Ch IV+) ─────────────────────────────────── */
.code-block {
  background: #141312;
  border: 0.5px solid #2e2c28;
  border-radius: 3px;
  margin: 36px 0;
  overflow: hidden;
}

.code-block-label {
  display: block;
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.06em;
  color: #6e6a62;
  background: #1c1a16;
  border-bottom: 0.5px solid #2e2c28;
  padding: 7px 14px;
}

.code-block pre {
  font-family: "DM Mono", monospace;
  font-size: 12.5px;
  line-height: 1.75;
  color: #c0bbb2;
  margin: 0;
  white-space: pre;
  padding: 18px 24px;
  overflow-x: auto;
}

.code-block .cm { color: #5a5a52; }
.code-block .ck { color: var(--gold); }
.code-block .cs { color: #8fba8f; }

/* ── Architecture table (Ch IV) ──────────────────────────── */
.arch-table {
  width: 100%;
  border-collapse: collapse;
  margin: 36px 0;
  border: 0.5px solid var(--border-light);
  border-radius: 3px;
  overflow: hidden;
}

.arch-table th {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.13em;
  text-transform: uppercase;
  color: var(--ink-faint);
  padding: 12px 18px;
  text-align: left;
  border-bottom: 0.5px solid var(--border-light);
  background: rgba(0, 0, 0, 0.02);
}

.arch-table td {
  font-family: "Lora", serif;
  font-size: 14px;
  line-height: 1.55;
  padding: 14px 18px;
  border-bottom: 0.5px solid var(--border-light);
  vertical-align: top;
  color: var(--interior-text);
}

.arch-table tr:last-child td {
  border-bottom: none;
}

.arch-table td:first-child {
  font-family: "DM Mono", monospace;
  font-size: 11px;
  color: var(--gold-dark);
  white-space: nowrap;
}

.arch-table td:nth-child(2) {
  font-family: "DM Mono", monospace;
  font-size: 11px;
  color: var(--ink-muted);
  white-space: nowrap;
}

/* Allow / block lists */
.permission-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1px;
  background: var(--border-light);
  border: 0.5px solid var(--border-light);
  border-radius: 3px;
  overflow: hidden;
  margin: 32px 0;
}

.permission-col {
  background: var(--interior-bg);
  padding: 20px 22px;
}

.permission-col-label {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  margin-bottom: 14px;
}

.permission-col-label.allow {
  color: #4a7c4a;
}
.permission-col-label.block {
  color: #8a4a4a;
}

.permission-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.permission-list li {
  font-family: "DM Mono", monospace;
  font-size: 12px;
  line-height: 1.4;
  padding-left: 18px;
  position: relative;
  color: var(--ink-muted);
}

.allow .permission-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: #4a7c4a;
  font-size: 10px;
}

.block .permission-list li::before {
  content: "✕";
  position: absolute;
  left: 0;
  color: #8a4a4a;
  font-size: 10px;
}

/* ── Timeline (Ch VI) ────────────────────────────────────── */
.timeline {
  display: flex;
  flex-direction: column;
  margin-top: 8px;
}

.timeline-item {
  display: grid;
  grid-template-columns: 130px 1fr;
  gap: 36px;
  padding: 32px 0;
  border-bottom: 0.5px solid var(--border-light);
}

.timeline-item:last-child {
  border-bottom: none;
}

.timeline-period {
  font-family: "DM Mono", monospace;
  font-size: 11px;
  color: var(--ink-faint);
  line-height: 1.6;
  padding-top: 3px;
}

.timeline-role {
  font-family: "DM Sans", sans-serif;
  font-size: 15px;
  font-weight: 500;
  color: var(--interior-text);
  margin-bottom: 3px;
}

.timeline-company {
  font-family: "DM Mono", monospace;
  font-size: 11px;
  color: var(--gold-dark);
  letter-spacing: 0.04em;
  margin-bottom: 14px;
}

.timeline-bullets {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.timeline-bullets li {
  font-family: "Lora", serif;
  font-size: 14px;
  line-height: 1.65;
  color: var(--ink-muted);
  padding-left: 18px;
  position: relative;
}

.timeline-bullets li::before {
  content: "–";
  position: absolute;
  left: 0;
  color: var(--ink-faint);
  font-family: "DM Mono", monospace;
}

.timeline-note {
  font-family: "Lora", serif;
  font-style: italic;
  font-size: 13px;
  color: var(--ink-faint);
  margin-top: 10px;
}

/* ── Capability table (Ch II) ────────────────────────────── */
.cap-table {
  width: 100%;
  border-collapse: collapse;
  margin: 36px 0;
  border: 0.5px solid var(--border-light);
  border-radius: 3px;
  overflow: hidden;
}

.cap-table th {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.13em;
  text-transform: uppercase;
  color: var(--ink-faint);
  padding: 11px 18px;
  text-align: left;
  border-bottom: 0.5px solid var(--border-light);
  background: rgba(0, 0, 0, 0.02);
}

.cap-table td {
  font-family: "Lora", serif;
  font-size: 14px;
  line-height: 1.5;
  padding: 13px 18px;
  border-bottom: 0.5px solid var(--border-light);
  vertical-align: top;
  color: var(--interior-text);
}

.cap-table tr:last-child td {
  border-bottom: none;
}

.cap-table td:first-child {
  font-family: "DM Mono", monospace;
  font-size: 12px;
  color: var(--gold-dark);
  white-space: nowrap;
}

.cap-badge {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 2px 7px;
  border-radius: 2px;
  white-space: nowrap;
}

.cap-badge.customer {
  color: #4a7c4a;
  background: rgba(74, 124, 74, 0.08);
  border: 0.5px solid rgba(74, 124, 74, 0.25);
}

.cap-badge.admin {
  color: #8a5a2a;
  background: rgba(196, 154, 60, 0.08);
  border: 0.5px solid rgba(196, 154, 60, 0.25);
}

/* Layer heading inside chapter */
.layer-heading {
  font-family: "DM Serif Display", serif;
  font-size: 22px;
  color: var(--interior-text);
  margin: 44px 0 16px;
  padding-top: 36px;
  border-top: 0.5px solid var(--gold-divider);
}

.layer-num {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--gold);
  display: block;
  margin-bottom: 6px;
}

/* ── Pipeline stages (Ch IV) ─────────────────────────────── */
.pipeline-stages {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  background: var(--border-light);
  border: 0.5px solid var(--border-light);
  border-radius: 3px;
  overflow: hidden;
  margin: 36px 0;
}

.pipeline-stage {
  background: var(--interior-bg);
  padding: 20px 20px 24px;
}

.pipeline-stage-num {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 8px;
}

.pipeline-stage-name {
  font-family: "DM Serif Display", serif;
  font-size: 20px;
  color: var(--interior-text);
  line-height: 1;
  margin-bottom: 6px;
}

.pipeline-stage-budget {
  font-family: "DM Mono", monospace;
  font-size: 11px;
  color: var(--gold);
  margin-bottom: 14px;
}

.pipeline-stage-desc {
  font-family: "Lora", serif;
  font-size: 13px;
  line-height: 1.6;
  color: var(--ink-muted);
  padding-top: 12px;
  border-top: 0.5px solid var(--border-light);
}

.pipeline-stage-desc code {
  font-family: "DM Mono", monospace;
  font-size: 11px;
  background: rgba(154, 111, 42, 0.08);
  color: var(--gold-dark);
  padding: 1px 4px;
  border-radius: 2px;
}

/* ── Security callout (Ch IV) ────────────────────────────── */
.security-callout {
  margin: 32px 0;
  padding: 20px 24px;
  border-left: 2px solid #c84b4a;
  background: rgba(200, 75, 74, 0.04);
}

.security-callout-label {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #a33d3d;
  margin-bottom: 10px;
}

.security-callout p {
  font-family: "Lora", serif;
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-muted);
  margin: 0;
}

/* ── Outcome metrics grid ────────────────────────────────── */
.outcome-metrics {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--border-light);
  border: 0.5px solid var(--border-light);
  border-radius: 3px;
  overflow: hidden;
  margin: 28px 0 36px;
}

.outcome-metric {
  background: var(--interior-bg);
  padding: 20px 22px;
}

.outcome-metric-val {
  font-family: "DM Serif Display", serif;
  font-size: 28px;
  color: var(--interior-text);
  line-height: 1;
  margin-bottom: 6px;
}

.outcome-metric-label {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-faint);
  line-height: 1.5;
}

/* ── Design-property cards (Ch V) ─────────────────────────── */
.principle-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--border-light);
  border: 0.5px solid var(--border-light);
  border-radius: 3px;
  overflow: hidden;
  margin: 32px 0 12px;
}

.principle-card {
  background: var(--interior-bg);
  padding: 22px 24px 22px;
  display: flex;
  flex-direction: column;
}

.principle-card.full {
  grid-column: 1 / -1;
}

.principle-num {
  font-family: "DM Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.16em;
  color: var(--gold);
  margin-bottom: 10px;
}

.principle-title {
  font-family: "DM Serif Display", serif;
  font-size: 19px;
  line-height: 1.2;
  color: var(--interior-text);
  margin: 0 0 10px;
}

.principle-body {
  font-family: "Lora", serif;
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--ink-muted);
  margin: 0;
}

.principle-body code {
  font-family: "DM Mono", monospace;
  font-size: 11.5px;
  background: rgba(154, 111, 42, 0.08);
  color: var(--gold-dark);
  padding: 1px 4px;
  border-radius: 2px;
}

.principle-foil {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 0.5px dashed var(--border-light);
}

.principle-foil-label {
  font-family: "DM Mono", monospace;
  font-size: 9.5px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-faint);
  display: block;
  margin-bottom: 6px;
}

.principle-foil p {
  font-family: "Lora", serif;
  font-style: italic;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--ink-faint);
  margin: 0;
}

/* ── Limitations ledger (Ch V) ────────────────────────────── */
.limitation-ledger {
  margin: 28px 0 12px;
  border: 0.5px solid var(--border-light);
  border-radius: 3px;
  overflow: hidden;
}

.limitation-row {
  display: grid;
  grid-template-columns: 230px 1fr;
  border-bottom: 0.5px solid var(--border-light);
}

.limitation-row:last-child {
  border-bottom: none;
}

.limitation-name {
  padding: 18px 20px;
  background: rgba(196, 154, 60, 0.045);
  border-right: 0.5px solid var(--border-light);
  font-family: "DM Sans", sans-serif;
  font-weight: 500;
  font-size: 14px;
  line-height: 1.35;
  color: var(--interior-text);
}

.limitation-glyph {
  display: block;
  font-family: "DM Mono", monospace;
  font-size: 11px;
  color: #a37a2a;
  letter-spacing: 0.06em;
  margin-bottom: 6px;
}

.limitation-detail {
  padding: 18px 22px;
}

.limitation-detail p {
  font-family: "Lora", serif;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--ink-muted);
  margin: 0;
}

.limitation-detail code {
  font-family: "DM Mono", monospace;
  font-size: 11.5px;
  background: rgba(154, 111, 42, 0.08);
  color: var(--gold-dark);
  padding: 1px 4px;
  border-radius: 2px;
}

.limitation-direction {
  margin-top: 12px;
  padding-top: 10px;
  border-top: 0.5px dashed var(--border-light);
  font-family: "DM Mono", monospace;
  font-size: 11.5px;
  line-height: 1.55;
  color: var(--ink-muted);
  letter-spacing: 0.01em;
}

.limitation-direction strong {
  font-weight: 500;
  color: var(--gold);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-right: 10px;
  font-size: 10px;
}

/* ── OS Architecture diagram (Ch II) ───────────────────────── */
.os-diagram-wrap {
  margin: 44px 0;
  border-radius: 4px;
  overflow: hidden;
}
.os-diagram-wrap svg {
  width: 100%;
  height: auto;
  display: block;
}
.os-node {
  opacity: 0;
}
.os-arrow {
  stroke-dasharray: 300;
  stroke-dashoffset: 300;
}
.os-config-band {
  opacity: 0;
}

.os-animate .os-node {
  animation: osNodeIn 0.5s ease forwards;
}
.os-animate .os-arrow {
  animation: osArrowDraw 0.45s ease forwards;
}
.os-animate .os-config-band {
  animation: osFadeIn 0.55s ease forwards;
}

/* staggered delays — nodes */
.os-animate .os-node:nth-child(1)  { animation-delay: 0.05s; }
.os-animate .os-node:nth-child(2)  { animation-delay: 0.15s; }
.os-animate .os-node:nth-child(3)  { animation-delay: 0.25s; }
.os-animate .os-node:nth-child(4)  { animation-delay: 0.35s; }
.os-animate .os-node:nth-child(5)  { animation-delay: 0.45s; }
.os-animate .os-node:nth-child(6)  { animation-delay: 0.55s; }
/* staggered delays — arrows */
.os-animate .os-arrow:nth-child(1) { animation-delay: 0.3s; }
.os-animate .os-arrow:nth-child(2) { animation-delay: 0.4s; }
.os-animate .os-arrow:nth-child(3) { animation-delay: 0.5s; }
.os-animate .os-arrow:nth-child(4) { animation-delay: 0.6s; }
.os-animate .os-arrow:nth-child(5) { animation-delay: 0.7s; }

.os-config-band { animation-delay: 0.75s; }

@keyframes osNodeIn {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}
@keyframes osArrowDraw {
  to { stroke-dashoffset: 0; }
}
@keyframes osFadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}

/* hover highlight on node groups */
.os-node-group { cursor: default; }
.os-node-group:hover .os-node-rect {
  filter: brightness(1.08);
}

/* ── OS Lifecycle diagram (Ch II) ───────────────────────────── */
.os-lifecycle-wrap {
  margin: 36px 0 44px;
  border-radius: 4px;
  overflow: hidden;
}
.os-lifecycle-wrap svg {
  width: 100%;
  height: auto;
  display: block;
}

/* ── Paper texture on cream interior ────────────────────── */
.chapter.interior {
  background-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' width='256' height='256'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/><feColorMatrix type='saturate' values='0'/></filter><rect width='256' height='256' filter='url(%23n)' opacity='0.04'/></svg>");
  background-repeat: repeat;
  background-size: 256px;
}

/* ── Mobile ──────────────────────────────────────────────── */
@media (max-width: 768px) {
  /* Use the full content width — the 66.667% cap is print-page styling
     that leaves a tiny column on phone widths. */
  .toc-inner,
  .ch-inner {
    max-width: 100%;
    padding: 24px 18px 56px;
  }

  /* Display type */
  .page-title { font-size: 28px; }
  .ch-title { font-size: 30px; line-height: 1.1; }
  .ch-eyebrow,
  .page-eyebrow {
    font-size: 9.5px;
    margin-bottom: 10px;
  }
  .ch-header {
    margin-bottom: 32px;
    padding-bottom: 20px;
  }

  /* Prose */
  .ch-body {
    font-size: 15.5px;
    line-height: 1.75;
  }
  .ch-body p + p { margin-top: 18px; }

  .drop-cap::first-letter {
    font-size: 3.6em;
    line-height: 0.78;
    margin: 0.05em 0.08em 0 0;
  }

  .pull-quote {
    margin: 32px 0;
    padding-left: 18px;
  }
  .pull-quote p { font-size: 17px; line-height: 1.5; }

  .aside {
    margin: 28px 0;
    padding: 16px 18px;
  }
  .aside p { font-size: 13.5px; }

  /* Stat row: 4-col → 2x2 */
  .stat-row {
    grid-template-columns: repeat(2, 1fr);
    margin: 32px 0;
  }
  .stat-row-cell {
    padding: 16px 14px;
    border-right: 0.5px solid var(--border-light);
    border-bottom: 0.5px solid var(--border-light);
  }
  .stat-row-cell:nth-child(2n) { border-right: none; }
  .stat-row-cell:nth-last-child(-n+2) { border-bottom: none; }
  .stat-row-num { font-size: 22px; }

  /* TOC entries stack */
  .toc-entry {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
    padding: 18px 0;
  }
  .toc-num { padding-top: 0; }
  .toc-body {
    flex-direction: column;
    align-items: flex-start;
    width: 100%;
    gap: 4px;
  }
  .toc-chapter-title {
    font-size: 20px;
    white-space: normal;
  }
  .toc-leaders { display: none; }

  /* Agent (Ch III) */
  .agent-header {
    flex-wrap: wrap;
    gap: 10px;
  }
  .agent-name { font-size: 26px; }

  /* Capability / arch tables: shrink padding, allow first column to wrap */
  .cap-table,
  .arch-table {
    margin: 28px 0;
  }
  .cap-table td,
  .arch-table td {
    padding: 11px 12px;
    font-size: 13px;
  }
  .cap-table th,
  .arch-table th {
    padding: 10px 12px;
  }
  .cap-table td:first-child,
  .arch-table td:first-child,
  .arch-table td:nth-child(2) {
    white-space: normal;
    word-break: break-word;
    font-size: 11px;
  }

  /* Code block: smaller, tighter; horizontal scroll already on */
  .code-block { margin: 28px 0; }
  .code-block pre {
    font-size: 11.5px;
    padding: 14px 16px;
  }

  /* Pipeline stages: 4 → 1 */
  .pipeline-stages {
    grid-template-columns: 1fr;
    margin: 28px 0;
  }
  .pipeline-stage { padding: 16px 18px 18px; }

  /* Outcome metrics: 3 → 1 */
  .outcome-metrics {
    grid-template-columns: 1fr;
  }
  .outcome-metric { padding: 16px 18px; }
  .outcome-metric-val { font-size: 24px; }

  /* Principles: 2 → 1 */
  .principle-grid {
    grid-template-columns: 1fr;
    margin: 24px 0;
  }
  .principle-card { padding: 18px 20px; }
  .principle-title { font-size: 18px; }

  /* Permission grid: 2 → 1 */
  .permission-grid {
    grid-template-columns: 1fr;
    margin: 24px 0;
  }
  .permission-col { padding: 16px 18px; }

  /* Timeline (Ch VI): stack period over role */
  .timeline-item {
    grid-template-columns: 1fr;
    gap: 8px;
    padding: 22px 0;
  }
  .timeline-period { padding-top: 0; }
  .timeline-company { margin-bottom: 10px; }

  /* Limitation ledger: stack name/detail */
  .limitation-row {
    grid-template-columns: 1fr;
  }
  .limitation-name {
    border-right: none;
    border-bottom: 0.5px solid var(--border-light);
    padding: 14px 16px;
  }
  .limitation-detail { padding: 14px 16px; }

  .layer-heading {
    font-size: 19px;
    margin: 36px 0 14px;
    padding-top: 28px;
  }

  .outcome-section {
    margin-top: 36px;
    padding-top: 24px;
  }

  .agent-section {
    margin-top: 36px;
    padding-top: 28px;
  }

  .ch-subhead { font-size: 17px; }
}

@media (max-width: 480px) {
  .toc-inner,
  .ch-inner {
    padding: 20px 14px 48px;
  }

  .ch-title { font-size: 26px; line-height: 1.12; }
  .page-title { font-size: 24px; }

  .ch-body { font-size: 15px; }

  .drop-cap::first-letter { font-size: 3em; }

  .pull-quote p { font-size: 15.5px; }

  .stat-row-num { font-size: 20px; }
  .stat-row-label { font-size: 9.5px; }

  .agent-name { font-size: 22px; }

  .pipeline-stage-name { font-size: 18px; }

  .code-block pre {
    font-size: 11px;
    padding: 12px 14px;
  }

  .cap-table td,
  .arch-table td {
    padding: 10px 10px;
    font-size: 12.5px;
  }
}