@font-face {
  font-family: Fraunces;
  src: url('../assets/fonts/fraunces-700.ttf') format('truetype');
  font-weight: 700;
  font-display: swap;
}

@font-face {
  font-family: 'Noto Serif SC';
  src: url('../assets/fonts/noto-serif-sc-600.ttf') format('truetype');
  font-weight: 600;
  font-display: swap;
}

:root {
  --ink: #242821;
  --paper: #e9e3d6;
  --paper-card: #e1dbce;
  --paper-tint: #ded8cb;
  --muted: #65695e;
  --rule: #777c6948;
  --rule-strong: #777c6988;
  --accent-sage: #617562;
  --accent-olive: #6b5833;
  --accent-dark: #1b201a;
  --mono: 'JetBrains Mono', 'DM Mono', 'SFMono-Regular', Menlo, monospace;
  --display: 'Noto Serif SC', 'Songti SC', Georgia, serif;
  --wordmark: Fraunces, Georgia, serif;
  --body: 'Helvetica Neue', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  font-family: var(--body);
  color: var(--ink);
  background: var(--paper);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; overflow-x: hidden; }
body { margin: 0; background: var(--paper); color: var(--ink); line-height: 1.6; overflow-x: hidden; width: 100%; }
a { color: inherit; text-decoration: none; }
a:focus-visible, button:focus-visible { outline: 2px solid var(--ink); outline-offset: 4px; }
img { display: block; max-width: 100%; }
figure, h1, h2, h3, h4, p, ul, ol { margin: 0; }

.mono { font-family: var(--mono); }

/* Layout Shell */
.case-page {
  min-height: 100vh;
  background: radial-gradient(circle at 85% 12%, #dad5c7 0%, transparent 45%), var(--paper);
}

.case-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  max-width: 1440px;
  margin: auto;
  padding: 28px 48px;
  border-bottom: 1px solid var(--rule);
}

.case-brand {
  font: 700 26px/1 var(--wordmark);
  letter-spacing: -.06em;
}

.case-header-nav {
  display: flex;
  align-items: center;
  gap: 28px;
}

.case-header-nav a {
  font-size: 13px;
  color: var(--muted);
  transition: color .2s;
}

.case-header-nav a:hover {
  color: var(--ink);
}

.case-back {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  min-height: 40px;
  padding-bottom: 2px;
  border-bottom: 1.5px solid var(--ink);
  font-size: 14px;
  font-weight: 600;
}

.case-content {
  max-width: 1440px;
  margin: auto;
  padding: 0 48px;
}

/* Hero Section */
.case-hero {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
  align-items: center;
  gap: 64px;
  padding: 72px 0 64px;
}

.case-kicker {
  font-size: 15px;
  font-family: var(--mono), var(--display);
  font-weight: 600;
  letter-spacing: .08em;
  color: #4b5243;
  text-transform: uppercase;
}

.case-kicker-row {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 12px 16px;
}

.case-kicker-row .case-kicker {
  margin: 0;
  font-family: var(--display);
  font-size: 15px;
  font-weight: 600;
  letter-spacing: .06em;
  color: #3e4637;
}

.case-demo-badge {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  font-family: var(--display);
  font-size: 13px;
  font-weight: 400;
  color: #5c6454;
  background: rgba(97, 117, 98, 0.06);
  border: 1px solid #c2baa8;
  padding: 2px 10px;
  border-radius: 2px;
  line-height: 1.5;
  letter-spacing: 0.03em;
}

.case-demo-badge::before {
  content: "※";
  font-family: var(--display);
  font-size: 12px;
  color: var(--accent-sage, #617562);
  line-height: 1;
}


.case-hero h1 {
  font: 700 clamp(44px, 4.8vw, 76px)/1.08 var(--wordmark), var(--display);
  letter-spacing: -.045em;
  margin: 22px 0 20px;
}

.case-line {
  font: 600 clamp(20px, 2vw, 28px)/1.5 var(--display);
  color: #3b4234;
  margin-bottom: 20px;
}

.case-summary {
  font-size: 16px;
  line-height: 1.85;
  color: #52594a;
  max-width: 680px;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 20px;
  margin-top: 32px;
  flex-wrap: wrap;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  background: var(--ink);
  color: #f6f2ea;
  border: 1px solid var(--ink);
  border-radius: 3px;
  font-size: 14px;
  font-weight: 600;
  transition: background .2s, transform .2s;
}

.btn-primary:hover {
  background: #394235;
  transform: translateY(-2px);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 20px;
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--rule-strong);
  border-radius: 3px;
  font-size: 14px;
  font-weight: 500;
  transition: border-color .2s, background .2s;
}

.btn-secondary:hover {
  border-color: var(--ink);
  background: #ded7c7;
}

/* Hero Key Metrics Poster Card */
.hero-metric-board {
  padding: 24px;
  background: #e2dbce;
  border: 1px solid #c4c7b8;
  border-radius: 4px;
  box-shadow: 10px 14px 0 #b3b6a7, 14px 20px 32px #24282115;
  transform: rotate(0.8deg);
}

.hero-metric-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--rule);
  font-size: 11px;
  font-family: var(--mono);
  color: var(--muted);
}

.hero-metric-stack {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin: 20px 0;
}

.hero-metric-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 14px 16px;
  background: #ebe6dc;
  border: 1px solid #cfd2c3;
  border-radius: 3px;
}

.hero-metric-row .metric-label {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.hero-metric-row .metric-label strong {
  font-size: 14px;
  font-weight: 700;
  color: var(--ink);
}

.hero-metric-row .metric-label span {
  font-size: 11px;
  color: var(--muted);
  font-family: var(--mono);
}

.hero-metric-row .metric-values {
  text-align: right;
}

.hero-metric-row del {
  display: block;
  font-size: 12px;
  color: #92998a;
  font-family: var(--mono);
}

.hero-metric-row em {
  font-style: normal;
  font-size: 24px;
  font-weight: 800;
  font-family: var(--mono);
  color: #1a2217;
  line-height: 1.1;
}

.hero-metric-badge {
  display: inline-block;
  font-size: 10px;
  font-family: var(--mono);
  padding: 2px 6px;
  background: #d5ded0;
  border: 1px solid #aebcaa;
  color: #31442e;
  border-radius: 2px;
  margin-top: 2px;
}

.hero-metric-footer {
  padding-top: 14px;
  border-top: 1px dashed #b5b9a8;
  font-size: 12px;
  color: var(--muted);
  line-height: 1.6;
}

/* Case Facts Grid */
.case-facts {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 28px;
  padding: 32px 0;
  border-block: 1px solid var(--rule);
}

.case-facts div {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.case-facts span {
  font-size: 11px;
  font-family: var(--mono);
  color: var(--muted);
  letter-spacing: .08em;
  text-transform: uppercase;
}

.case-facts strong {
  font-size: 14px;
  line-height: 1.65;
  color: #262c22;
}

/* Chapter Base */
.case-chapter {
  padding: 88px 0;
  border-top: 1px solid var(--rule);
}

.chapter-heading {
  display: grid;
  grid-template-columns: minmax(220px, .45fr) minmax(0, 1.55fr);
  column-gap: 6%;
  align-items: start;
  margin-bottom: 48px;
}

.chapter-heading .case-kicker {
  font-size: 16px;
  font-weight: 700;
  letter-spacing: .08em;
  color: #31372b;
  padding-top: 6px;
}

.chapter-heading h2 {
  font: 600 clamp(32px, 3.6vw, 54px)/1.28 var(--display);
  letter-spacing: -.035em;
  color: #1f251d;
}

.chapter-heading > p:last-child {
  grid-column: 2;
  font-size: 16px;
  line-height: 1.9;
  color: var(--muted);
  max-width: 820px;
  margin-top: 20px;
}

/* Broad point grid */
.point-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
  margin-top: 40px;
}

.point-card {
  padding: 28px 24px;
  background: var(--paper-card);
  border: 1px solid #c7c9ba;
  border-top: 3px solid var(--ink);
  border-radius: 3px;
  display: flex;
  flex-direction: column;
}

.point-card.highlight {
  border-top-color: var(--accent-sage);
  background: #dbe2d6;
}

.point-card > span {
  font-size: 11px;
  font-family: var(--mono);
  letter-spacing: .08em;
  color: var(--muted);
}

.point-card h3 {
  font: 600 22px/1.4 var(--display);
  margin: 16px 0 12px;
  color: #1f261c;
}

.point-card p {
  font-size: 14px;
  line-height: 1.8;
  color: #495042;
}

.point-stat-badge {
  margin-top: auto;
  padding-top: 18px;
  border-top: 1px dashed #b9bca9;
  font-family: var(--mono);
  font-size: 12px;
  color: #555d4c;
}

.point-stat-badge strong {
  display: block;
  font-size: 15px;
  color: var(--ink);
  margin-top: 4px;
}

/* FDE Deep Dive Box */
.fde-contrast-box {
  margin-top: 48px;
  padding: 32px 36px;
  background: #252a23;
  color: #f2ece0;
  border-radius: 4px;
  border: 1px solid #484f42;
}

.fde-contrast-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 20px;
  padding-bottom: 20px;
  border-bottom: 1px solid #444b3e;
}

.fde-contrast-header h3 {
  font: 600 clamp(22px, 2.2vw, 30px)/1.35 var(--display);
  color: #f7f3eb;
}

.fde-contrast-header span {
  font-family: var(--mono);
  font-size: 12px;
  color: #adb5a3;
  letter-spacing: .06em;
}

.fde-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 28px;
  margin-top: 28px;
}

.fde-col h4 {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 10px;
  color: #e5decb;
}

.fde-col p {
  font-size: 13px;
  line-height: 1.8;
  color: #bdc5b5;
}

.fde-col strong {
  color: #f0e6cb;
}

/* Architecture Topology Flow */
.topology-flow {
  margin-top: 44px;
  padding: 28px;
  background: #ded7c9;
  border: 1px solid #c0c4b4;
  border-radius: 4px;
}

.topology-title {
  font-size: 11px;
  font-family: var(--mono);
  color: var(--muted);
  letter-spacing: .1em;
  text-transform: uppercase;
  margin-bottom: 20px;
}

.topology-nodes {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 12px;
  align-items: center;
}

.topo-node {
  padding: 16px 14px;
  background: #eae5da;
  border: 1px solid #c2c6b6;
  border-radius: 3px;
  text-align: center;
  position: relative;
}

.topo-node.active {
  border-color: #556a53;
  background: #dce4d5;
}

.topo-step {
  font-size: 10px;
  font-family: var(--mono);
  color: var(--muted);
}

.topo-node h4 {
  font-size: 13px;
  font-weight: 700;
  color: var(--ink);
  margin: 6px 0 4px;
}

.topo-node p {
  font-size: 11px;
  color: #52594a;
  line-height: 1.4;
}

/* Pull-quote Thesis */
.case-thesis {
  display: grid;
  grid-template-columns: minmax(220px, .45fr) minmax(0, 1.55fr);
  column-gap: 6%;
  padding: 64px 0;
  border-top: 1px solid var(--rule);
}

.case-thesis h2 {
  font: 600 clamp(28px, 3.2vw, 44px)/1.35 var(--display);
  letter-spacing: -.03em;
  color: #1e241c;
}

.case-thesis p {
  font-size: 16px;
  line-height: 1.9;
  color: var(--muted);
  margin-top: 18px;
  max-width: 800px;
}

/* Tab Switcher */
.case-tabs {
  display: flex;
  gap: 12px;
  margin-bottom: 36px;
  border-bottom: 1px solid var(--rule);
  padding-bottom: 14px;
  overflow-x: auto;
  max-width: 100%;
  -webkit-overflow-scrolling: touch;
}

.tab-btn {
  padding: 10px 20px;
  font-family: var(--body);
  font-size: 14px;
  font-weight: 600;
  color: var(--muted);
  background: none;
  border: 1px solid transparent;
  border-radius: 3px;
  cursor: pointer;
  transition: all .2s;
  white-space: nowrap;
}

.tab-btn:hover {
  color: var(--ink);
  background: #ded7c7;
}

.tab-btn.active {
  color: var(--ink);
  background: #d8dfd1;
  border-color: #aebbaa;
}

.tab-panel {
  display: none;
}

.tab-panel.active {
  display: block;
  animation: tabFadeIn .22s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes tabFadeIn {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Value Formula Card */
.value-formula-card {
  margin-top: 40px;
  padding: 28px 32px;
  background: #ebe6db;
  border: 1px solid #c7cab8;
  border-radius: 4px;
}

.value-formula-card h4 {
  font-size: 12px;
  font-family: var(--mono);
  letter-spacing: .08em;
  color: var(--muted);
  text-transform: uppercase;
  margin-bottom: 18px;
}

.formula-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 32px;
}

.formula-item strong {
  display: block;
  font-size: 15px;
  color: var(--ink);
  margin-bottom: 8px;
}

.formula-item p {
  font-size: 13px;
  line-height: 1.75;
  color: #555c4d;
}

/* Scope Comparison (Did vs Did Not) */
.scope-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 36px;
  margin-top: 36px;
}

.scope-col-header {
  display: flex;
  align-items: center;
  gap: 10px;
  padding-bottom: 16px;
  border-bottom: 2px solid var(--ink);
  font: 600 18px var(--display);
}

.scope-col-header.muted {
  border-bottom-color: #8c9282;
  color: #585f4f;
}

.scope-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-top: 20px;
}

.scope-item {
  padding: 18px 20px;
  background: #e2dcd0;
  border: 1px solid #c6c9b8;
  border-radius: 3px;
}

.scope-item.scope-done {
  border-left: 4px solid var(--accent-sage);
  background: #dce3d5;
}

.scope-item.scope-skip {
  border-left: 4px solid #8e9484;
}

.scope-item h4 {
  font-size: 15px;
  font-weight: 700;
  color: #21281c;
  margin-bottom: 6px;
}

.scope-item p {
  font-size: 13px;
  line-height: 1.75;
  color: #4b5243;
}

/* Timeline: A Day at the Shop */
.day-timeline {
  display: flex;
  flex-direction: column;
  gap: 48px;
  margin-top: 40px;
}

.day-period {
  padding: 32px;
  background: #ded7ca;
  border: 1px solid #c1c5b4;
  border-radius: 4px;
}

.period-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding-bottom: 16px;
  border-bottom: 1px solid #b7bca9;
  margin-bottom: 24px;
}

.period-header h3 {
  font: 600 24px/1.3 var(--display);
  color: #1e261a;
}

.period-tag {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--muted);
}

.step-card-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.step-card {
  padding: 16px 14px;
  background: #ebe6dc;
  border: 1px solid #c8cbba;
  border-radius: 3px;
}

.step-card span {
  font-size: 10px;
  font-family: var(--mono);
  color: var(--muted);
}

.step-card strong {
  display: block;
  font-size: 13px;
  color: var(--ink);
  margin: 6px 0 4px;
}

.step-card p {
  font-size: 11px;
  color: #555d4e;
  line-height: 1.5;
}

.period-callout {
  margin-top: 20px;
  padding: 12px 16px;
  background: #d4dcce;
  border-left: 3px solid var(--accent-sage);
  font-size: 13px;
  color: #344030;
  line-height: 1.7;
}

/* Voice Reporter Simulation */
.voice-simulator {
  margin-top: 24px;
  background: #232820;
  color: #eae5d7;
  border-radius: 4px;
  border: 1px solid #434c3d;
  overflow: hidden;
}

.voice-sim-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 20px;
  background: #1b2019;
  border-bottom: 1px solid #384232;
  font-size: 12px;
  font-family: var(--mono);
}

.voice-sim-body {
  padding: 24px 28px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
}

.voice-bubble {
  padding: 18px 20px;
  background: #313a2d;
  border: 1px solid #4a5744;
  border-radius: 4px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.voice-bubble-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 11px;
  font-family: var(--mono);
  color: #a4b39b;
}

.voice-bubble blockquote {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: #f7f3eb;
  font-family: var(--body);
}

.voice-parsed-card {
  padding: 18px 20px;
  background: #ebe6db;
  color: var(--ink);
  border: 1px solid #c8cbba;
  border-radius: 4px;
}

.parsed-card-title {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-bottom: 10px;
  border-bottom: 1px solid #c6cabb;
  font-size: 13px;
  font-weight: 700;
}

.parsed-card-badge {
  font-size: 10px;
  font-family: var(--mono);
  padding: 2px 6px;
  background: #d4ded0;
  border: 1px solid #abb9a6;
  color: #2b3b27;
  border-radius: 2px;
}

.parsed-stats-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin: 14px 0;
  text-align: center;
}

.parsed-stats-item {
  padding: 8px;
  background: #ded7cb;
  border: 1px solid #c2c6b6;
  border-radius: 2px;
}

.parsed-stats-item span {
  font-size: 10px;
  color: var(--muted);
  font-family: var(--mono);
}

.parsed-stats-item strong {
  display: block;
  font-size: 18px;
  font-family: var(--mono);
  color: var(--ink);
}

.wage-locked-banner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 14px;
  background: #d4ded0;
  border: 1px solid #adc1a7;
  border-radius: 2px;
  font-size: 12px;
  color: #2a3a25;
  font-weight: 600;
}

.wage-locked-banner strong {
  font-size: 17px;
  font-family: var(--mono);
  color: #1b2e17;
}

/* Screen showcase */
.screen-showcase-container {
  margin-top: 36px;
}

.screen-card-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(0, .65fr);
  gap: 32px;
  align-items: start;
}

.screen-mock-frame {
  padding: 16px 20px 14px;
  background: #e2dbce;
  border: 1px solid #c3c6b5;
  border-radius: 6px;
  box-shadow: 0 10px 30px rgba(36, 40, 33, 0.06);
  display: flex;
  flex-direction: column;
}

.screen-frame-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 11px;
  font-family: var(--mono);
  color: var(--muted);
  padding-bottom: 10px;
  border-bottom: 1px solid #c4c7b8;
}

.screen-window-dots {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.screen-window-dots span {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: #bfbba9;
  display: inline-block;
}

.screen-window-dots span:nth-child(1) { background: #cf7c6d; }
.screen-window-dots span:nth-child(2) { background: #d9b15b; }
.screen-window-dots span:nth-child(3) { background: #7ea378; }

.screen-image-wrap {
  margin: 14px 0 12px;
  border-radius: 4px;
  overflow: hidden;
  border: 1px solid #b8bca9;
  background: #111418;
  position: relative;
  display: block;
}

.screen-image-wrap img {
  width: 100%;
  height: auto;
  display: block;
  transition: transform .3s ease;
}

.screen-image-wrap:hover img {
  transform: scale(1.01);
}

.screen-image-zoom-tip {
  position: absolute;
  right: 12px;
  bottom: 12px;
  background: rgba(17, 20, 24, 0.75);
  backdrop-filter: blur(4px);
  color: #f1ede4;
  font-family: var(--mono);
  font-size: 11px;
  padding: 4px 8px;
  border-radius: 3px;
  opacity: 0;
  transition: opacity .2s ease;
  pointer-events: none;
}

.screen-image-wrap:hover .screen-image-zoom-tip {
  opacity: 1;
}

.screen-frame-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 11px;
  font-family: var(--mono);
  color: var(--muted);
  padding-top: 10px;
  border-top: 1px solid #c4c7b8;
}

.screen-frame-footer a {
  color: var(--ink);
  font-weight: 600;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.screen-points-col {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.screen-point-box {
  padding: 18px 20px;
  background: #e5ded2;
  border: 1px solid #c8cbba;
  border-radius: 3px;
}

.screen-point-box.alert {
  border-left: 4px solid #944b3c;
}

.screen-point-box.warn {
  border-left: 4px solid #a37f37;
}

.screen-point-box.verify {
  border-left: 4px solid var(--accent-sage);
}

.screen-point-box.action {
  border-left: 4px solid var(--ink);
}

.screen-point-box h4 {
  font-size: 14px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 6px;
}

.screen-point-box p {
  font-size: 13px;
  line-height: 1.75;
  color: #4f5746;
}

/* Quantified Results Table */
.results-table-wrapper {
  margin-top: 40px;
  overflow-x: auto;
  border: 1px solid #bfc3b2;
  border-radius: 4px;
  background: #ebe6dc;
}

.results-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 13px;
}

.results-table th {
  padding: 14px 18px;
  background: #ded7c9;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--muted);
  text-transform: uppercase;
  border-bottom: 1px solid #bfc3b2;
}

.results-table td {
  padding: 16px 18px;
  border-bottom: 1px solid #cfd3c2;
  color: #2b3225;
}

.results-table tr:last-child td {
  border-bottom: 0;
}

.results-table del {
  color: #92998a;
  font-family: var(--mono);
}

.results-table .stat-val {
  font-weight: 700;
  font-family: var(--mono);
  color: #1a2316;
}

.results-table .stat-gain {
  font-weight: 700;
  font-family: var(--mono);
  color: var(--accent-sage);
  text-align: right;
}

/* Retrospective 3 Columns */
.retrospective-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 28px;
  margin-top: 40px;
}

.retro-col {
  padding: 28px 24px;
  background: #e2dbcf;
  border: 1px solid #c4c7b6;
  border-top: 3px solid var(--ink);
  border-radius: 3px;
}

.retro-col h3 {
  font: 600 20px/1.3 var(--display);
  margin-bottom: 20px;
  color: #1b2216;
}

.retro-item {
  padding-bottom: 16px;
  margin-bottom: 16px;
  border-bottom: 1px solid #c7caba;
}

.retro-item:last-child {
  padding-bottom: 0;
  margin-bottom: 0;
  border-bottom: 0;
}

.retro-item strong {
  display: block;
  font-size: 13px;
  color: var(--ink);
  margin-bottom: 4px;
}

.retro-item p {
  font-size: 12px;
  line-height: 1.7;
  color: #555d4c;
}

/* Footer & Navigation */
.case-navigation {
  display: flex;
  justify-content: space-between;
  align-items: start;
  gap: 25px;
  border-top: 1px solid var(--rule);
  padding: 44px 0 100px;
}

.case-navigation > a {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.case-navigation > a:last-child {
  text-align: right;
}

.case-navigation span {
  font-size: 11px;
  font-family: var(--mono);
  color: var(--muted);
}

.case-navigation strong {
  font: 700 22px var(--wordmark), var(--display);
  color: var(--ink);
}

.case-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
  padding: 28px 48px;
  background: #ded7ca;
  border-top: 1px solid var(--rule);
  font-size: 12px;
  color: var(--muted);
}

.case-footer a {
  color: var(--ink);
  border-bottom: 1px solid var(--ink);
}

/* ============================================================ */
/* Architecture Mindmap & Five-Layer Flywheel (Native Theme)   */
/* ============================================================ */
.arch-duality-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 48px;
}

.arch-duality-card {
  padding: 28px 28px;
  border-radius: 4px;
  border: 1px solid #c7c9ba;
  background: var(--paper-card);
  display: flex;
  flex-direction: column;
  transition: transform .2s, border-color .2s;
}

.arch-duality-card:hover {
  border-color: var(--ink);
  transform: translateY(-2px);
}

.arch-duality-card.blue {
  border-top: 4px solid #3b6e8c;
  background: #e1e7eb;
}

.arch-duality-card.amber {
  border-top: 4px solid #b3732c;
  background: #ebe3d5;
}

.arch-duality-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.arch-duality-badge {
  font-size: 11px;
  font-family: var(--mono);
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 2px;
}

.arch-duality-card.blue .arch-duality-badge {
  background: rgba(59, 110, 140, 0.15);
  color: #24495e;
}

.arch-duality-card.amber .arch-duality-badge {
  background: rgba(179, 115, 44, 0.15);
  color: #6d4212;
}

.arch-duality-card h4 {
  font-size: 18px;
  font-family: var(--display);
  color: var(--ink);
  margin-bottom: 8px;
}

.arch-duality-card p {
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
  margin-bottom: 16px;
  flex: 1;
}

.arch-duality-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.arch-duality-tags span {
  font-size: 11px;
  font-family: var(--mono);
  padding: 3px 8px;
  background: rgba(0, 0, 0, 0.05);
  border: 1px solid rgba(0, 0, 0, 0.06);
  border-radius: 2px;
  color: var(--ink);
}

/* Flywheel Accordion */
.arch-flywheel-wrap {
  margin-bottom: 56px;
}

.arch-sub-heading {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--rule);
  padding-bottom: 12px;
  gap: 16px;
}

.flywheel-header-actions {
  display: flex;
  align-items: center;
  gap: 14px;
}

.arch-sub-tip {
  font-size: 12px;
  color: var(--muted);
}

.flywheel-toggle-all-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  font-family: var(--body);
  font-size: 12.5px;
  font-weight: 600;
  color: var(--ink);
  background: #eae4d7;
  border: 1px solid #c7c9ba;
  border-radius: 4px;
  cursor: pointer;
  user-select: none;
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

.flywheel-toggle-all-btn:hover {
  background: #ded7c7;
  border-color: var(--ink);
  color: var(--ink);
  transform: translateY(-1px);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.flywheel-toggle-all-btn:active {
  transform: translateY(0);
}

.flywheel-toggle-all-btn .toggle-icon {
  font-size: 11px;
  color: var(--accent-sage);
  font-weight: 700;
  transition: transform 0.2s ease;
}

.flywheel-toggle-all-btn.is-expanded {
  background: #dce5da;
  border-color: #a7bca8;
}

.flywheel-toggle-all-btn.is-expanded .toggle-icon {
  color: #3b5e40;
}

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

.flywheel-layer {
  background: var(--paper-card);
  border: 1px solid #c7c9ba;
  border-radius: 4px;
  overflow: hidden;
  transition: border-color .2s, box-shadow .2s;
}

.flywheel-layer:hover {
  border-color: var(--ink);
}

.flywheel-layer-header {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 16px 20px;
  cursor: pointer;
  user-select: none;
  background: #e5dfd2;
  transition: background .2s;
}

.flywheel-layer-header:hover {
  background: #ded7c8;
}

.flywheel-badge {
  font-size: 11px;
  font-family: var(--mono);
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 2px;
}

.flywheel-badge.b1 { background: rgba(59, 110, 140, 0.16); color: #24495e; }
.flywheel-badge.b2 { background: rgba(124, 88, 133, 0.16); color: #583362; }
.flywheel-badge.b3 { background: rgba(179, 115, 44, 0.16); color: #6d4212; }
.flywheel-badge.b4 { background: rgba(74, 84, 130, 0.16); color: #2c3359; }
.flywheel-badge.b5 { background: rgba(80, 120, 81, 0.16); color: #2f5430; }

.flywheel-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
  flex: 1;
}

.flywheel-sub-note {
  font-size: 12px;
  color: var(--muted);
}

.flywheel-toggle {
  font-size: 12px;
  color: var(--muted);
  transition: transform .25s ease;
}

.flywheel-layer.open .flywheel-toggle {
  transform: rotate(90deg);
}

.flywheel-layer-body {
  max-height: 0;
  overflow: hidden;
  transition: max-height .35s ease, padding .35s ease;
  padding: 0 20px;
}

.flywheel-layer.open .flywheel-layer-body {
  max-height: 900px;
  padding: 20px;
  border-top: 1px solid var(--rule);
}

.flywheel-node-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 14px;
}

.flywheel-node-card {
  background: var(--paper);
  border: 1px solid #d1cdbf;
  border-radius: 3px;
  padding: 16px;
  transition: transform .2s, border-color .2s;
}

.flywheel-node-card:hover {
  border-color: var(--ink);
  transform: translateY(-2px);
}

.flywheel-node-icon {
  font-size: 20px;
  margin-bottom: 6px;
}

.flywheel-node-name {
  font-size: 14px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 4px;
}

.flywheel-node-desc {
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

/* MCP Specification Box */
.mcp-protocol-box {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 12px;
}

.mcp-card {
  background: var(--paper);
  border: 1px solid #d1cdbf;
  border-radius: 3px;
  padding: 16px;
}

.mcp-card.resources { border-left: 3px solid #6b5887; }
.mcp-card.tools { border-left: 3px solid #b3732c; }

.mcp-card-title {
  font-size: 13px;
  font-weight: 700;
  margin-bottom: 10px;
  font-family: var(--mono);
  color: var(--ink);
}

.mcp-item {
  font-size: 13px;
  color: var(--muted);
  padding: 5px 0;
  display: flex;
  align-items: center;
  gap: 8px;
  border-bottom: 1px dashed rgba(0, 0, 0, 0.06);
}

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

.mcp-item code {
  font-family: var(--mono);
  font-size: 12px;
  background: rgba(0, 0, 0, 0.04);
  padding: 1px 4px;
  border-radius: 2px;
  color: var(--ink);
}

.mcp-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  flex-shrink: 0;
}

.mcp-dot.purple { background: #6b5887; }
.mcp-dot.amber { background: #b3732c; }

.mcp-footer-note {
  font-size: 12px;
  font-family: var(--mono);
  color: var(--muted);
  padding-top: 6px;
}

/* Technical Specs & Timeline */
.arch-specs-wrap {
  margin-top: 48px;
}

.arch-flow-timeline {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-top: 8px;
}

.arch-flow-step {
  background: var(--paper-card);
  border: 1px solid #c7c9ba;
  border-radius: 3px;
  padding: 18px 16px;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: transform .2s, border-color .2s;
}

.arch-flow-step:hover {
  border-color: var(--ink);
  transform: translateY(-2px);
}

.arch-flow-num {
  font-size: 22px;
  font-family: var(--mono);
  font-weight: 700;
  color: #9ea492;
  line-height: 1;
  margin-bottom: 10px;
}

.arch-flow-main strong {
  display: block;
  font-size: 14px;
  color: var(--ink);
  margin-bottom: 6px;
}

.arch-flow-main p {
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
  margin-bottom: 12px;
}

.arch-flow-tag {
  display: inline-block;
  font-size: 11px;
  font-family: var(--mono);
  color: var(--ink);
  background: #ded7c8;
  padding: 2px 6px;
  border-radius: 2px;
  align-self: flex-start;
}

/* API Table Method Tags */
.method-tag {
  font-size: 11px;
  font-family: var(--mono);
  font-weight: 700;
  padding: 2px 6px;
  border-radius: 2px;
}

.method-tag.get { background: #d7e4d8; color: #2e6133; }
.method-tag.post { background: #f0e1cf; color: #8a4e14; }

.arch-api-note {
  font-size: 12px;
  color: var(--muted);
  margin-top: 14px;
}

/* Responsive Media Queries */
@media (max-width: 1024px) {
  .case-header, .case-content, .case-footer { padding-inline: 32px; }
  .case-hero { grid-template-columns: 1fr; gap: 48px; }
  .chapter-heading { grid-template-columns: 1fr; gap: 16px; }
  .chapter-heading > p:last-child { grid-column: 1; margin-top: 0; }
  .case-thesis { grid-template-columns: 1fr; gap: 16px; }
  .point-grid { grid-template-columns: 1fr; }
  .fde-grid { grid-template-columns: 1fr; gap: 20px; }
  .topology-nodes { grid-template-columns: 1fr; gap: 8px; }
  .case-facts { grid-template-columns: 1fr 1fr; gap: 20px; }
  .formula-grid { grid-template-columns: 1fr; gap: 20px; }
  .scope-grid { grid-template-columns: 1fr; gap: 28px; }
  .step-card-grid { grid-template-columns: 1fr 1fr; gap: 12px; }
  .voice-sim-body { grid-template-columns: 1fr; }
  .screen-card-grid { grid-template-columns: 1fr; }
  .retrospective-grid { grid-template-columns: 1fr; }
  .arch-duality-grid { grid-template-columns: 1fr; }
  .mcp-protocol-box { grid-template-columns: 1fr; }
  .arch-flow-timeline { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 700px) {
  .case-header, .case-content, .case-footer { padding-inline: 20px; }
  .case-brand { font-size: 20px; }
  .case-header-nav { display: none; }
  .case-back { font-size: 13px; white-space: nowrap; }
  .case-hero { padding: 48px 0; }
  .case-hero h1 { font-size: 36px; }
  .case-line { font-size: 18px; }
  .case-facts { grid-template-columns: 1fr; }
  .step-card-grid { grid-template-columns: 1fr; }
  .case-chapter { padding: 56px 0; }
  .chapter-heading h2 { font-size: 28px; }
  .case-thesis h2 { font-size: 24px; }
  .case-navigation { flex-direction: column; gap: 24px; }
  .case-navigation > a:last-child { text-align: left; }
  .case-footer { flex-direction: column; align-items: flex-start; gap: 12px; }
  .arch-sub-heading { flex-direction: column; align-items: flex-start; gap: 8px; }
  .arch-flow-timeline { grid-template-columns: 1fr; }
  .flywheel-sub-note { display: none; }
}

/* Real System Demo Section */
.real-system-demo-section {
  border-top: 1px solid var(--rule);
  padding: 64px 0 80px;
}

.demo-video-wrapper {
  display: flex;
  flex-direction: column;
  gap: 32px;
  margin-top: 24px;
}

.demo-video-frame {
  background: #1e221f;
  border: 1px solid rgba(0, 0, 0, 0.15);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 20px 48px rgba(0, 0, 0, 0.18);
}

.demo-video-frame .screen-frame-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 20px;
  background: #141715;
  color: #9da397;
  font-size: 13px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.live-badge {
  color: #52c41a;
  font-weight: 600;
  font-size: 12px;
  letter-spacing: 0.04em;
}

.video-container {
  width: 100%;
  background: #000;
  line-height: 0;
  position: relative;
}

.video-container video {
  width: 100%;
  height: auto;
  display: block;
  outline: none;
}

.timeline-quicknav {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  padding: 14px 20px;
  background: #181c19;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.quicknav-title {
  font-size: 13px;
  color: #8c9386;
  font-weight: 500;
  margin-right: 4px;
}

.tnav-pill {
  font-family: var(--mono);
  font-size: 12px;
  padding: 6px 14px;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: #cfd4c8;
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

.tnav-pill:hover {
  background: rgba(255, 255, 255, 0.14);
  color: #fff;
  border-color: rgba(255, 255, 255, 0.3);
}

.tnav-pill.active {
  background: var(--accent-sage);
  border-color: var(--accent-sage);
  color: #fff;
  font-weight: 600;
  box-shadow: 0 2px 8px rgba(97, 117, 98, 0.4);
}

.demo-milestones-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.milestone-card {
  padding: 18px 20px;
  background: var(--paper-card);
  border: 1px solid var(--rule);
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
}

.milestone-card:hover {
  background: #fdfaf3;
  border-color: var(--accent-sage);
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.05);
}

.milestone-card.active {
  background: #fff;
  border-color: var(--accent-sage);
  box-shadow: 0 0 0 1px var(--accent-sage), 0 8px 20px rgba(0, 0, 0, 0.06);
}

.milestone-card .ms-time {
  font-size: 12px;
  font-weight: 700;
  color: var(--accent-sage);
  margin-bottom: 6px;
}

.milestone-card h4 {
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 6px;
  line-height: 1.4;
}

.milestone-card p {
  font-size: 13px;
  color: var(--muted);
  line-height: 1.6;
}

@media (max-width: 960px) {
  .demo-milestones-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 600px) {
  .demo-milestones-grid {
    grid-template-columns: 1fr;
  }
  .timeline-quicknav {
    flex-direction: column;
    align-items: stretch;
  }
}

/* ============================================================ */
/* FLOATING ARTICLE TABLE OF CONTENTS (右侧浮动目录导航) */
/* ============================================================ */
.floating-toc-wrapper {
  position: fixed;
  right: 28px;
  top: 110px;
  z-index: 120;
  opacity: 0;
  visibility: hidden;
  transform: translateX(16px);
  transition: opacity 0.3s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.3s cubic-bezier(0.16, 1, 0.3, 1),
              visibility 0.3s;
  pointer-events: none;
}

.floating-toc-wrapper.visible {
  opacity: 1;
  visibility: visible;
  transform: translateX(0);
  pointer-events: auto;
}

.toc-card {
  width: 220px;
  background: rgba(250, 247, 240, 0.94);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid rgba(119, 124, 105, 0.28);
  border-radius: 10px;
  box-shadow: 0 12px 32px rgba(25, 29, 24, 0.08), 0 2px 6px rgba(0, 0, 0, 0.04);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

.toc-progress-track {
  width: 100%;
  height: 3px;
  background: rgba(0, 0, 0, 0.06);
  position: relative;
  overflow: hidden;
}

.toc-progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent-sage), #4a7751);
  transition: width 0.12s linear;
}

.toc-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 14px 8px;
  border-bottom: 1px solid rgba(119, 124, 105, 0.15);
}

.toc-header-title {
  display: flex;
  align-items: center;
  gap: 6px;
  font-family: var(--display);
  font-size: 13px;
  font-weight: 700;
  color: var(--ink);
  letter-spacing: -0.01em;
}

.toc-header-icon {
  font-size: 13px;
  color: var(--accent-sage);
  font-weight: 800;
}

.toc-header-meta {
  display: flex;
  align-items: center;
  gap: 8px;
}

.toc-progress-percent {
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 600;
  color: var(--accent-sage);
}

.toc-collapse-btn {
  background: rgba(0, 0, 0, 0.04);
  border: 1px solid rgba(0, 0, 0, 0.08);
  border-radius: 4px;
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  line-height: 1;
  color: var(--muted);
  cursor: pointer;
  padding: 0;
  transition: all 0.15s ease;
}

.toc-collapse-btn:hover {
  background: rgba(0, 0, 0, 0.08);
  color: var(--ink);
  border-color: rgba(0, 0, 0, 0.2);
}

.toc-nav-list {
  padding: 6px 8px;
  display: flex;
  flex-direction: column;
  gap: 2px;
  max-height: calc(85vh - 170px);
  overflow-y: auto;
  scrollbar-width: thin;
}

.toc-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 5px 10px;
  border-radius: 5px;
  text-decoration: none;
  transition: all 0.15s ease;
  position: relative;
}

.toc-item:hover {
  background: rgba(0, 0, 0, 0.04);
}

.toc-item:hover .toc-label {
  color: var(--ink);
}

.toc-num {
  font-family: var(--mono);
  font-size: 10.5px;
  font-weight: 600;
  color: var(--muted);
  flex-shrink: 0;
}

.toc-label {
  font-size: 12px;
  color: #555b4e;
  line-height: 1.4;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: color 0.15s ease;
}

.toc-item.active {
  background: rgba(103, 124, 104, 0.12);
}

.toc-item.active::before {
  content: '';
  position: absolute;
  left: 2px;
  top: 6px;
  bottom: 6px;
  width: 2.5px;
  background: var(--accent-sage);
  border-radius: 2px;
}

.toc-item.active .toc-num {
  color: var(--accent-sage);
  font-weight: 700;
}

.toc-item.active .toc-label {
  color: var(--ink);
  font-weight: 600;
}

.toc-footer {
  padding: 7px 14px 9px;
  border-top: 1px solid rgba(119, 124, 105, 0.12);
  display: flex;
  align-items: center;
  justify-content: flex-end;
}

.toc-back-top-btn {
  font-family: inherit;
  font-size: 11px;
  color: var(--muted);
  background: none;
  border: none;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 0;
  transition: color 0.15s ease;
}

.toc-back-top-btn:hover {
  color: var(--ink);
}

/* Collapsed Trigger Pill */
.toc-trigger-pill {
  display: none;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  background: rgba(250, 247, 240, 0.94);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid rgba(119, 124, 105, 0.32);
  border-radius: 999px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
  cursor: pointer;
  user-select: none;
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
  font-family: inherit;
}

.toc-trigger-pill:hover {
  background: #fff;
  border-color: var(--ink);
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.12);
}

.pill-icon {
  font-size: 13px;
}

.pill-text {
  font-size: 12px;
  font-weight: 600;
  color: var(--ink);
}

.pill-percent {
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 700;
  color: var(--accent-sage);
  margin-left: 2px;
}

/* Collapsed State on Wrapper */
.floating-toc-wrapper.is-collapsed .toc-card {
  display: none;
}

.floating-toc-wrapper.is-collapsed .toc-trigger-pill {
  display: flex;
}

/* Mobile & Tablet & Laptop Responsive Adaptations */
@media (max-width: 1600px) {
  .floating-toc-wrapper {
    right: 20px;
    top: auto;
    bottom: 24px;
    transform: translateY(16px);
  }

  .floating-toc-wrapper.visible {
    transform: translateY(0);
  }

  .floating-toc-wrapper:not(.is-mobile-expanded) .toc-card {
    display: none;
  }

  .floating-toc-wrapper:not(.is-mobile-expanded) .toc-trigger-pill {
    display: flex;
  }

  .floating-toc-wrapper.is-mobile-expanded .toc-card {
    display: flex;
    position: absolute;
    bottom: 48px;
    right: 0;
    width: 230px;
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.18);
  }

  .floating-toc-wrapper.is-mobile-expanded .toc-trigger-pill {
    display: none;
  }
}

/* ============================================================ */
/* SECTION EXTENSIONS & ARCHITECTURAL REFACTORING */
/* ============================================================ */

/* 1. Research Source Block (需求溯源与现场决策) */
.research-source-block {
  margin-top: 40px;
  padding-top: 32px;
  border-top: 1px dashed var(--rule-strong);
}

.research-source-heading {
  margin-bottom: 22px;
}

.research-source-heading .case-kicker {
  font-size: 13px;
  color: var(--accent-sage);
  margin-bottom: 6px;
  letter-spacing: .06em;
}

.research-source-heading h3 {
  font-family: var(--display);
  font-size: clamp(20px, 2.2vw, 26px);
  color: var(--ink);
  font-weight: 600;
  line-height: 1.35;
}

/* 2. Human-in-the-Loop Boundary Box (人机分工边界) */
.hitl-boundary-box {
  background: var(--paper-card);
  border: 1px solid #c8c2b2;
  border-radius: 4px;
  padding: 16px 20px;
  margin-top: 12px;
}

.hitl-boundary-title {
  font-size: 11px;
  font-family: var(--mono);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: #6c7365;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.hitl-boundary-title::before {
  content: "§";
  color: var(--accent-sage);
}

.hitl-boundary-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  font-size: 12px;
}

.hitl-col {
  display: flex;
  flex-direction: column;
}

.hitl-col-header {
  font-weight: 700;
  font-size: 12.5px;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.hitl-col-header.ai {
  color: #2f6b3b;
}

.hitl-col-header.human {
  color: #24588d;
}

.hitl-col-header.fallback {
  color: #8c2a2a;
}

.hitl-col-desc {
  color: #555c4d;
  line-height: 1.65;
  font-size: 12px;
}

@media (max-width: 768px) {
  .hitl-boundary-grid {
    grid-template-columns: 1fr;
    gap: 14px;
  }
  .hitl-col {
    padding-bottom: 10px;
    border-bottom: 1px dashed var(--rule);
  }
  .hitl-col:last-child {
    border-bottom: none;
    padding-bottom: 0;
  }
}

/* 3. Screen Point Mini Eval Stat (Screen 04 离线评测标注) */
.screen-point-eval-note {
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px dashed #cfc8b8;
  font-size: 11.5px;
  color: #525a4a;
  line-height: 1.55;
}

.screen-point-eval-note strong {
  color: #2a613c;
  font-family: var(--mono);
  font-weight: 700;
}

/* 4. Retrospective AI Eval Section (复盘 AI 质量保障体系) */
.retro-eval-section {
  margin: 48px 0 36px;
  padding-top: 36px;
  border-top: 1px solid var(--rule-strong);
}

.retro-eval-header {
  margin-bottom: 20px;
}

.retro-eval-header .case-kicker {
  font-size: 14px;
  color: var(--accent-sage);
  margin-bottom: 6px;
  letter-spacing: .06em;
}

.retro-eval-header h3 {
  font-family: var(--display);
  font-size: clamp(22px, 2.4vw, 28px);
  color: var(--ink);
  font-weight: 600;
  line-height: 1.35;
}

/* ============================================================ */
/* RAG FLOW · 私有知识库实时引用链路 (REFACTORED WORKBENCH) */
/* ============================================================ */
.rag-workbench {
  background: var(--paper-card);
  border: 1px solid var(--rule-strong);
  border-radius: 14px;
  padding: 28px;
  margin-top: 18px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.04);
  position: relative;
  overflow: hidden;
}

/* 顶部控制栏：场景切换与仿真指令 */
.rag-control-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  padding-bottom: 20px;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--rule);
}

.rag-scenario-selector {
  display: inline-flex;
  background: rgba(0, 0, 0, 0.05);
  padding: 4px;
  border-radius: 30px;
  gap: 4px;
}

.rag-scenario-btn {
  border: none;
  background: transparent;
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  color: var(--muted);
  cursor: pointer;
  transition: all .2s ease;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.rag-scenario-btn:hover {
  color: var(--ink);
}

.rag-scenario-btn.active {
  background: var(--ink);
  color: #f7f5f0;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}

.rag-telemetry-cluster {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.rag-telemetry-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--mono);
  font-size: 11px;
  background: rgba(255, 255, 255, 0.6);
  border: 1px solid var(--rule);
  padding: 4px 10px;
  border-radius: 6px;
  color: var(--muted);
}

.rag-telemetry-pill strong {
  color: #245e38;
}

.rag-simulate-btn {
  background: var(--accent-sage);
  color: #fff;
  border: none;
  padding: 6px 14px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: all .2s;
  box-shadow: 0 2px 6px rgba(97, 117, 98, 0.25);
}

.rag-simulate-btn:hover {
  background: #4f6350;
  transform: translateY(-1px);
}

.rag-simulate-btn:active {
  transform: translateY(0);
}

.rag-simulate-btn.is-simulating {
  background: #8e5b1e;
  pointer-events: none;
}

/* 4 阶段端到端数据流转管道 (Stage Pipeline) */
.rag-pipeline-container {
  margin-bottom: 28px;
}

.rag-pipeline-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.rag-pipeline-title {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .08em;
  font-family: var(--mono);
  color: var(--muted);
  font-weight: 700;
}

.rag-pipeline-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  position: relative;
}

.rag-pipeline-card {
  background: #fbf9f4;
  border: 1px solid #dcd6c8;
  border-radius: 10px;
  padding: 12px 14px;
  position: relative;
  transition: all .3s cubic-bezier(0.16, 1, 0.3, 1);
}

.rag-pipeline-card::after {
  content: "→";
  position: absolute;
  right: -12px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 14px;
  color: #a8a395;
  font-weight: 700;
  z-index: 2;
}

.rag-pipeline-card:last-child::after {
  display: none;
}

.rag-pipeline-card.active-step {
  border-color: #2d6a4f;
  background: #f4faf5;
  box-shadow: 0 0 0 2px rgba(45, 106, 79, 0.2);
}

.rag-step-num {
  font-family: var(--mono);
  font-size: 10px;
  font-weight: 700;
  color: #8b8577;
  margin-bottom: 4px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.rag-step-name {
  font-size: 13px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 4px;
}

.rag-step-detail {
  font-size: 11px;
  color: var(--muted);
  line-height: 1.5;
}

/* 双向交互证据链溯源看板 (Interactive Grounding Workbench) */
.rag-grounding-grid {
  display: grid;
  grid-template-columns: 1.05fr 40px 1.15fr;
  align-items: stretch;
  gap: 0;
  background: #fcfbf8;
  border: 1px solid #d8d2c4;
  border-radius: 12px;
  padding: 20px;
}

/* 左侧：四层私域知识切片 */
.rag-sources-col {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.rag-col-header {
  font-size: 11px;
  font-family: var(--mono);
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--muted);
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 2px;
}

.rag-source-card {
  border: 1.5px solid #ded8cb;
  border-radius: 10px;
  padding: 12px 14px;
  background: #ffffff;
  transition: all .25s ease;
  cursor: pointer;
  position: relative;
}

.rag-source-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
}

/* 各层专属主题色 */
.rag-source-card[data-layer="L1"] {
  border-left: 4px solid #2d6a4f;
}
.rag-source-card[data-layer="L2"] {
  border-left: 4px solid #1e5f8e;
}
.rag-source-card[data-layer="L3"] {
  border-left: 4px solid #5b3f8e;
}
.rag-source-card[data-layer="L4"] {
  border-left: 4px solid #8e5b1e;
}

.rag-source-card.is-highlighted {
  box-shadow: 0 0 0 2px #1b201a, 0 6px 16px rgba(0, 0, 0, 0.12);
  transform: translateX(4px);
}
.rag-source-card[data-layer="L1"].is-highlighted {
  border-color: #2d6a4f;
  background: #f2fbf4;
}
.rag-source-card[data-layer="L2"].is-highlighted {
  border-color: #1e5f8e;
  background: #f0f7fd;
}
.rag-source-card[data-layer="L3"].is-highlighted {
  border-color: #5b3f8e;
  background: #f7f3fd;
}
.rag-source-card[data-layer="L4"].is-highlighted {
  border-color: #8e5b1e;
  background: #fdf7ee;
}

.rag-source-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 6px;
}

.rag-layer-tag {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-family: var(--mono);
  font-size: 10px;
  font-weight: 700;
  padding: 2px 7px;
  border-radius: 4px;
}

.rag-layer-tag.l1 { background: #e8f5e9; color: #2d6a4f; }
.rag-layer-tag.l2 { background: #e3f2fd; color: #1e5f8e; }
.rag-layer-tag.l3 { background: #f3e5f5; color: #5b3f8e; }
.rag-layer-tag.l4 { background: #fff3e0; color: #8e5b1e; }

.rag-meta-pills {
  display: flex;
  align-items: center;
  gap: 6px;
  font-family: var(--mono);
  font-size: 10px;
  color: #7a7e72;
}

.rag-latency-badge {
  background: rgba(0, 0, 0, 0.04);
  padding: 1px 5px;
  border-radius: 3px;
}

.rag-source-title {
  font-size: 12.5px;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 4px;
}

.rag-source-content {
  font-size: 11px;
  color: var(--muted);
  line-height: 1.55;
}

.rag-source-snippet {
  margin-top: 6px;
  padding: 6px 8px;
  background: rgba(0, 0, 0, 0.03);
  border-radius: 4px;
  font-family: var(--mono);
  font-size: 10.5px;
  color: #3b4235;
  border-left: 2px solid #b5af9f;
}

/* 视频时间戳与胶卷缩略指示 */
.rag-video-timestamp-pill {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  background: #1e5f8e;
  color: #fff;
  padding: 2px 8px;
  border-radius: 12px;
  font-family: var(--mono);
  font-size: 10px;
  font-weight: 600;
  margin-top: 4px;
}

/* 中间：链路流转脉冲与连线指示 */
.rag-bridge-col {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  position: relative;
}

.rag-bridge-line {
  position: absolute;
  top: 20px;
  bottom: 20px;
  width: 2px;
  background: linear-gradient(to bottom, transparent, #c7c1b1 15%, #c7c1b1 85%, transparent);
}

.rag-bridge-flow-indicator {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: #fff;
  border: 1.5px solid #a6a090;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  color: #4b5243;
  z-index: 2;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.08);
  transition: all .3s;
}

.rag-bridge-flow-indicator.is-flowing {
  background: #2d6a4f;
  color: #fff;
  border-color: #2d6a4f;
  box-shadow: 0 0 12px rgba(45, 106, 79, 0.4);
  animation: pulseFlow 1s infinite alternate;
}

@keyframes pulseFlow {
  from { transform: scale(1); }
  to { transform: scale(1.15); }
}

/* 右侧：Agent 终端决策与交互式引用标注 */
.rag-agent-col {
  display: flex;
  flex-direction: column;
}

.rag-terminal-box {
  background: #191c18;
  border-radius: 10px;
  padding: 16px 18px;
  color: #cfd6c7;
  font-size: 12px;
  line-height: 1.75;
  box-shadow: inset 0 2px 6px rgba(0, 0, 0, 0.4);
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.rag-terminal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 10px;
  margin-bottom: 12px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  font-family: var(--mono);
  font-size: 10px;
  color: #939b8c;
}

.rag-terminal-dots {
  display: flex;
  gap: 5px;
}

.rag-terminal-dots span {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #3e4438;
}

.rag-user-query-bubble {
  background: rgba(255, 255, 255, 0.07);
  border-left: 3px solid #6b8266;
  padding: 8px 12px;
  border-radius: 4px;
  font-size: 12px;
  color: #e8eee2;
  margin-bottom: 14px;
}

.rag-user-query-bubble strong {
  color: #a8d8a8;
  font-family: var(--mono);
  font-size: 10px;
  text-transform: uppercase;
  margin-right: 6px;
}

.rag-answer-body {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.rag-answer-row {
  padding: 8px 10px;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid transparent;
  transition: all .2s;
  cursor: pointer;
}

.rag-answer-row:hover,
.rag-answer-row.is-highlighted {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.2);
  transform: translateX(3px);
}

.rag-answer-row-title {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 4px;
}

.rag-citation-pill {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-family: var(--mono);
  font-size: 9.5px;
  font-weight: 700;
  padding: 1px 7px;
  border-radius: 12px;
  transition: all .2s;
}

.rag-citation-pill.c-l1 { background: #2d6a4f; color: #d4e8d4; }
.rag-citation-pill.c-l2 { background: #1e5f8e; color: #cbe3f7; }
.rag-citation-pill.c-l3 { background: #5b3f8e; color: #ebdcf9; }
.rag-citation-pill.c-l4 { background: #8e5b1e; color: #fce8cc; }

.rag-answer-row:hover .rag-citation-pill,
.rag-answer-row.is-highlighted .rag-citation-pill {
  filter: brightness(1.25);
  box-shadow: 0 0 8px currentColor;
}

/* 底部工程保障与自成长机制 */
.rag-engineering-pillars {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-top: 24px;
}

.rag-pillar-card {
  background: #f4efe4;
  border: 1px solid #d5cec0;
  border-radius: 10px;
  padding: 14px 16px;
}

.rag-pillar-card h4 {
  font-size: 12.5px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.rag-pillar-card p {
  font-size: 11px;
  color: var(--muted);
  line-height: 1.6;
}

@media (max-width: 1024px) {
  .rag-grounding-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }
  .rag-bridge-col {
    display: none;
  }
  .rag-pipeline-steps {
    grid-template-columns: repeat(2, 1fr);
  }
  .rag-pipeline-card::after {
    display: none;
  }
}

@media (max-width: 640px) {
  .rag-pipeline-steps {
    grid-template-columns: 1fr;
  }
  .rag-engineering-pillars {
    grid-template-columns: 1fr;
  }
  .rag-workbench {
    padding: 16px;
  }
}