:root {
  --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", sans-serif;
  --font-mono: "SF Mono", ui-monospace, Menlo, monospace;

  /* Light theme (WCAG AA+) */
  --bg-page: #f7f8fa;
  --bg-surface: #ffffff;
  --bg-elevated: #f0f2f5;
  --bg-code: #f3f4f6;
  --border-subtle: #d5dae2;
  --border-strong: #9ca6b5;

  --text-primary: #111827;
  --text-secondary: #4b5563;
  --text-muted: #5b6472;

  --accent-primary: #0f172a;
  --accent-primary-fg: #ffffff;

  --accent-green: #15803d;
  --accent-green-bg: #ecfdf3;
  --accent-green-border: #86efac;

  --accent-blue: #1d4ed8;
  --accent-blue-bg: #eff6ff;
  --accent-blue-border: #93c5fd;

  --accent-amber: #b45309;
  --accent-amber-bg: #fffbeb;
  --accent-amber-border: #fcd34d;

  --accent-violet: #6d28d9;
  --accent-violet-bg: #f5f3ff;
  --accent-violet-border: #c4b5fd;

  --accent-red: #b91c1c;
  --accent-red-bg: #fef2f2;
  --accent-red-border: #fca5a5;

  --accent-slate: #475569;

  --header-bg: rgba(247, 248, 250, 0.88);
  --shadow-sm: 0 1px 2px rgba(17, 24, 39, 0.05);
  --shadow-md: 0 6px 20px rgba(17, 24, 39, 0.07);
  --focus-ring: 0 0 0 3px rgba(29, 78, 216, 0.35);
}

[data-theme="dark"] {
  --bg-page: #0b0d12;
  --bg-surface: #13161e;
  --bg-elevated: #1a1f2b;
  --bg-code: #10131a;
  --border-subtle: #2b3242;
  --border-strong: #535f78;

  --text-primary: #f3f4f6;
  --text-secondary: #b4becd;
  --text-muted: #9aa5b5;

  --accent-primary: #f3f4f6;
  --accent-primary-fg: #0b0d12;

  --accent-green: #4ade80;
  --accent-green-bg: #0f291a;
  --accent-green-border: #22c55e;

  --accent-blue: #60a5fa;
  --accent-blue-bg: #10213d;
  --accent-blue-border: #3b82f6;

  --accent-amber: #fbbf24;
  --accent-amber-bg: #2b1f09;
  --accent-amber-border: #d97706;

  --accent-violet: #a78bfa;
  --accent-violet-bg: #1e1638;
  --accent-violet-border: #7c3aed;

  --accent-red: #f87171;
  --accent-red-bg: #2b1113;
  --accent-red-border: #ef4444;

  --accent-slate: #94a3b8;

  --header-bg: rgba(11, 13, 18, 0.88);
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.35);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.45);
  --focus-ring: 0 0 0 3px rgba(96, 165, 250, 0.45);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.55;
  color: var(--text-primary);
  background-color: var(--bg-page);
  overflow-x: hidden;
}

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

a {
  color: var(--accent-blue);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 8px;
  z-index: 200;
  padding: 8px 14px;
  background: var(--accent-primary);
  color: var(--accent-primary-fg);
  border-radius: 6px;
  font-size: 14px;
  font-weight: 600;
}

.skip-link:focus {
  left: 12px;
}

.container {
  width: 100%;
  max-width: 1160px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--header-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-subtle);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 60px;
  padding-top: 8px;
  padding-bottom: 8px;
}

.brand-group {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--text-primary);
  font-weight: 650;
  font-size: 16px;
  letter-spacing: -0.02em;
}

.wordmark:hover {
  text-decoration: none;
}

.fka-note {
  font-size: 12px;
  color: var(--text-muted);
  display: none;
}

@media (min-width: 980px) {
  .fka-note {
    display: inline;
  }
}

.badge {
  display: inline-flex;
  align-items: center;
  padding: 2px 7px;
  border-radius: 999px;
  font-size: 11px;
  font-weight: 600;
  font-family: var(--font-mono);
  border: 1px solid var(--border-subtle);
  background: var(--bg-surface);
  color: var(--text-secondary);
}

.badge-version {
  border-color: var(--accent-blue-border);
  background: var(--accent-blue-bg);
  color: var(--accent-blue);
}

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

.nav-link {
  font-size: 13.5px;
  font-weight: 500;
  color: var(--text-secondary);
  display: none;
  padding: 4px 0;
  border-bottom: 2px solid transparent;
}

.nav-link:hover,
.nav-link.is-active {
  color: var(--text-primary);
  text-decoration: none;
}

.nav-link.is-active {
  border-bottom-color: var(--accent-blue);
}

@media (min-width: 860px) {
  .nav-link {
    display: inline;
  }
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  height: 32px;
  padding: 0 10px;
  border: 1px solid var(--border-subtle);
  border-radius: 7px;
  background: var(--bg-surface);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 12.5px;
  font-weight: 500;
  cursor: pointer;
}

.theme-toggle:hover {
  border-color: var(--border-strong);
}

[data-theme="light"] .icon-moon,
[data-theme="dark"] .icon-sun {
  display: none;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 16px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  white-space: nowrap;
}

.btn:hover {
  text-decoration: none;
}

.btn-sm {
  height: 32px;
  padding: 0 12px;
  font-size: 13px;
}

.btn-primary {
  background: var(--accent-primary);
  color: var(--accent-primary-fg);
}

.btn-primary:hover {
  opacity: 0.9;
}

.btn-secondary {
  background: var(--bg-surface);
  color: var(--text-primary);
  border-color: var(--border-subtle);
}

.btn-secondary:hover {
  border-color: var(--border-strong);
}

/* Hero */
.hero {
  padding: 40px 0 36px;
  border-bottom: 1px solid var(--border-subtle);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  align-items: center;
}

@media (min-width: 960px) {
  .hero-grid {
    grid-template-columns: 1.28fr 0.92fr;
    gap: 32px;
  }
}

.hero-title {
  margin: 0 0 14px;
  font-size: clamp(28px, 3.9vw, 42px);
  line-height: 1.12;
  letter-spacing: -0.03em;
  font-weight: 700;
}

.hero-subtitle {
  margin: 0 0 22px;
  font-size: clamp(15.5px, 1.7vw, 18px);
  color: var(--text-secondary);
  max-width: 62ch;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 22px;
}

.fact-strip {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.fact-pill {
  font-family: var(--font-mono);
  font-size: 12px;
  padding: 5px 10px;
  border-radius: 6px;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
}

/* Boarding-Pass Analogy Card */
.analogy-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
  padding: 16px 18px;
  box-shadow: var(--shadow-sm);
}

.analogy-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px;
  padding-bottom: 10px;
  margin-bottom: 12px;
  border-bottom: 1px solid var(--border-subtle);
}

.analogy-kicker {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent-green);
}

.analogy-meta {
  font-size: 12px;
  color: var(--text-muted);
}

.analogy-rows {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.analogy-row {
  display: grid;
  grid-template-columns: 88px 1fr;
  gap: 10px;
  align-items: start;
}

.analogy-label {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 700;
  color: var(--text-muted);
  padding-top: 2px;
}

.analogy-compare {
  display: flex;
  flex-direction: column;
  gap: 2px;
  font-size: 13px;
}

.compare-old {
  color: var(--text-muted);
  text-decoration: line-through;
  font-size: 12.5px;
}

.compare-new {
  color: var(--text-primary);
}

.compare-new code {
  font-size: 12px;
  background: var(--bg-elevated);
  padding: 1px 4px;
  border-radius: 4px;
}

/* Sections */
.section {
  padding: 56px 0;
  border-bottom: 1px solid var(--border-subtle);
  scroll-margin-top: 64px;
}

.section-arch {
  padding-top: 40px;
}

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 22px;
}

.eyebrow {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--accent-blue);
}

.section-title {
  margin: 0;
  font-size: clamp(22px, 2.5vw, 28px);
  letter-spacing: -0.02em;
  line-height: 1.2;
}

.section-desc {
  margin: 0;
  max-width: 50ch;
  font-size: 14.5px;
  color: var(--text-secondary);
}

/* 2.1 Flow Tabs */
.flow-bar-sticky {
  position: sticky;
  top: 60px;
  z-index: 40;
  background: var(--bg-page);
  padding: 8px 0 12px;
}

@media (min-width: 768px) {
  .flow-bar-sticky {
    position: static;
    padding: 0 0 12px;
  }
}

.flow-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding: 5px;
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: 10px;
}

.flow-tab {
  flex: 1 1 auto;
  padding: 8px 12px;
  border: 1px solid transparent;
  border-radius: 7px;
  background: transparent;
  color: var(--text-secondary);
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  text-align: center;
  white-space: nowrap;
}

.flow-tab:hover {
  color: var(--text-primary);
}

.flow-tab[aria-selected="true"] {
  background: var(--bg-surface);
  color: var(--text-primary);
  border-color: var(--border-subtle);
  box-shadow: var(--shadow-sm);
}

/* Plain-English Flow Summary Banner */
.flow-banner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 14px;
  padding: 10px 14px;
  margin-bottom: 12px;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 10px;
}

.flow-banner-badge {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 5px;
  background: var(--accent-blue-bg);
  border: 1px solid var(--accent-blue-border);
  color: var(--accent-blue);
  white-space: nowrap;
}

.flow-banner-text {
  margin: 0;
  font-size: 13.5px;
  color: var(--text-primary);
}

/* 2.2 Desktop SVG Diagram */
.diagram-desktop-wrap {
  display: none;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 14px;
  padding: 16px;
  box-shadow: var(--shadow-sm);
}

@media (min-width: 768px) {
  .diagram-desktop-wrap {
    display: block;
  }
}

.arch-svg {
  width: 100%;
  height: auto;
  display: block;
  user-select: none;
}

.zone-box {
  fill: var(--accent-green-bg);
  fill-opacity: 0.45;
  stroke: var(--accent-green-border);
  stroke-width: 1.5;
  stroke-dasharray: 6 4;
}

.zone-label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.05em;
  fill: var(--accent-green);
}

.boundary-line {
  stroke: var(--border-strong);
  stroke-width: 1.5;
  stroke-dasharray: 5 5;
}

.boundary-label {
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 600;
  letter-spacing: 0.06em;
  fill: var(--text-muted);
}

.svg-node {
  cursor: pointer;
  transition: opacity 180ms ease;
}

.svg-zone {
  transition: opacity 180ms ease;
}

.svg-edge {
  transition: opacity 180ms ease;
}

.svg-node .node-bg {
  fill: var(--bg-surface);
  stroke: var(--border-subtle);
  stroke-width: 1.5;
}

.svg-node:hover .node-bg,
.svg-node:focus-visible .node-bg,
.svg-node.is-selected .node-bg,
.svg-node.is-step-hover .node-bg {
  stroke: var(--border-strong);
  stroke-width: 2.2;
}

.svg-node.is-selected .node-bg,
.svg-node.is-step-hover .node-bg {
  stroke: var(--accent-blue);
}

.svg-edge.is-step-hover .edge-path {
  stroke-width: 3.2;
}

.node-green .node-accent { fill: var(--accent-green); }
.node-blue .node-accent { fill: var(--accent-blue); }
.node-amber .node-accent { fill: var(--accent-amber); }
.node-violet .node-accent { fill: var(--accent-violet); }
.node-slate .node-accent { fill: var(--accent-slate); }

.node-title {
  font-size: 14.5px;
  font-weight: 700;
  fill: var(--text-primary);
}

.node-sub {
  font-size: 12px;
  fill: var(--text-secondary);
}

.node-line {
  font-size: 12px;
  fill: var(--text-secondary);
}

.node-inspect {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  fill: var(--accent-blue);
}

.pill-green-bg { fill: var(--accent-green-bg); stroke: var(--accent-green-border); stroke-width: 1; }
.pill-green-text { font-family: var(--font-mono); font-size: 11px; font-weight: 600; fill: var(--accent-green); }

.pill-blue-bg { fill: var(--accent-blue-bg); stroke: var(--accent-blue-border); stroke-width: 1; }
.pill-blue-text { font-family: var(--font-mono); font-size: 11px; font-weight: 600; fill: var(--accent-blue); }

.pill-amber-bg { fill: var(--accent-amber-bg); stroke: var(--accent-amber-border); stroke-width: 1; }
.pill-amber-text { font-family: var(--font-mono); font-size: 11px; font-weight: 600; fill: var(--accent-amber); }

.pill-violet-bg { fill: var(--accent-violet-bg); stroke: var(--accent-violet-border); stroke-width: 1; }
.pill-violet-text { font-family: var(--font-mono); font-size: 11px; font-weight: 600; fill: var(--accent-violet); }

.pill-neutral-bg { fill: var(--bg-elevated); stroke: var(--border-subtle); stroke-width: 1; }
.pill-neutral-text { font-family: var(--font-mono); font-size: 11px; font-weight: 500; fill: var(--text-secondary); }

.edge-path {
  fill: none;
  stroke-width: 2;
}

.edge-dashed {
  stroke-dasharray: 5 4;
}

.edge-blue .edge-path,
.edge-blue .edge-pulse { stroke: var(--accent-blue); }
.edge-green .edge-path,
.edge-green .edge-pulse { stroke: var(--accent-green); }
.edge-amber .edge-path,
.edge-amber .edge-pulse { stroke: var(--accent-amber); }
.edge-violet .edge-path,
.edge-violet .edge-pulse { stroke: var(--accent-violet); }

.edge-pulse {
  fill: none;
  stroke-width: 3;
  stroke-linecap: round;
  stroke-dasharray: 8 18;
  opacity: 0;
}

.arch-svg.is-pulsing .svg-edge:not(.is-dimmed) .edge-pulse {
  opacity: 0.9;
  animation: edgeFlow 1.3s linear infinite;
}

@keyframes edgeFlow {
  from {
    stroke-dashoffset: 26;
  }
  to {
    stroke-dashoffset: 0;
  }
}

.edge-pill-bg {
  fill: var(--bg-surface);
  stroke: var(--border-subtle);
  stroke-width: 1;
}

.edge-label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  fill: var(--text-primary);
}

.edge-seq[hidden] {
  display: none;
}

.seq-circle {
  fill: var(--accent-primary);
}

.seq-text {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  fill: var(--accent-primary-fg);
}

.is-dimmed {
  opacity: 0.16;
}

/* Mobile Stacked Diagram (< 768px) */
.diagram-mobile {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

@media (min-width: 768px) {
  .diagram-mobile {
    display: none;
  }
}

.mobile-zone {
  border: 1.5px dashed var(--accent-green-border);
  background: var(--accent-green-bg);
  border-radius: 12px;
  padding: 12px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: opacity 180ms ease;
}

.mobile-zone-title {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  color: var(--accent-green);
}

.mobile-node {
  width: 100%;
  text-align: left;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-top: 3px solid var(--border-strong);
  border-radius: 10px;
  padding: 12px 14px;
  color: var(--text-primary);
  font-family: var(--font-sans);
  display: flex;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  transition: opacity 180ms ease;
}

.mobile-node.node-green { border-top-color: var(--accent-green); }
.mobile-node.node-blue { border-top-color: var(--accent-blue); }
.mobile-node.node-amber { border-top-color: var(--accent-amber); }
.mobile-node.node-violet { border-top-color: var(--accent-violet); }
.mobile-node.node-slate { border-top-color: var(--accent-slate); }

.mobile-node.is-selected {
  border-color: var(--accent-blue);
  box-shadow: var(--focus-ring);
}

.mobile-node-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  font-size: 14.5px;
}

.mobile-inspect {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--accent-blue);
  font-weight: 600;
}

.mobile-node-sub,
.mobile-node-line {
  font-size: 12.5px;
  color: var(--text-secondary);
}

.mobile-pill {
  display: inline-block;
  align-self: flex-start;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  padding: 3px 8px;
  border-radius: 5px;
  border: 1px solid var(--border-subtle);
}

.mobile-pill.pill-green { background: var(--accent-green-bg); border-color: var(--accent-green-border); color: var(--accent-green); }
.mobile-pill.pill-blue { background: var(--accent-blue-bg); border-color: var(--accent-blue-border); color: var(--accent-blue); }
.mobile-pill.pill-amber { background: var(--accent-amber-bg); border-color: var(--accent-amber-border); color: var(--accent-amber); }
.mobile-pill.pill-violet { background: var(--accent-violet-bg); border-color: var(--accent-violet-border); color: var(--accent-violet); }
.mobile-pill.pill-neutral { background: var(--bg-elevated); color: var(--text-secondary); }

.mobile-boundary {
  text-align: center;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  color: var(--text-muted);
  padding: 6px 0;
  border-top: 1px dashed var(--border-strong);
  border-bottom: 1px dashed var(--border-strong);
}

.mobile-connectors-group {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.mobile-connector {
  text-align: center;
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 600;
  color: var(--text-secondary);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 6px;
  padding: 4px 8px;
  transition: opacity 180ms ease;
}

/* 2.3 Dynamic 3-Step Strip */
.flow-steps {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  margin-top: 16px;
}

@media (min-width: 768px) {
  .flow-steps {
    grid-template-columns: repeat(3, 1fr);
  }
}

.step-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 10px;
  padding: 16px;
  transition: border-color 140ms ease, box-shadow 140ms ease;
}

.step-card:hover,
.step-card.is-highlighted {
  border-color: var(--accent-blue-border);
  box-shadow: var(--shadow-sm);
}

.step-card-title {
  margin: 0 0 6px;
  font-size: 14.5px;
  font-weight: 700;
}

.step-card-body {
  margin: 0;
  font-size: 13.5px;
  color: var(--text-secondary);
}

.step-card-body code {
  font-size: 12px;
  background: var(--bg-elevated);
  padding: 1px 5px;
  border-radius: 4px;
}

/* 2.4 Node Detail Drawer */
.node-drawer {
  margin-top: 16px;
  background: var(--bg-surface);
  border: 1px solid var(--accent-blue-border);
  border-radius: 12px;
  padding: 18px 20px;
  box-shadow: var(--shadow-md);
}

.drawer-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 14px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-subtle);
}

.drawer-actions {
  display: flex;
  align-items: center;
  gap: 6px;
}

.drawer-kicker {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent-blue);
}

.drawer-title {
  margin: 2px 0 4px;
  font-size: 17px;
}

.drawer-plain {
  margin: 0;
  font-size: 13.5px;
  color: var(--text-secondary);
  max-width: 66ch;
}

.drawer-grid {
  margin: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

@media (min-width: 768px) {
  .drawer-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
  }
}

.drawer-row dt {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 700;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.drawer-row dd {
  margin: 0;
  font-size: 13.5px;
  color: var(--text-primary);
}

/* Section 3: Artifact Inspector + Tamper Simulator */
.inspector-shell {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.inspector-tabs {
  display: flex;
  flex-wrap: wrap;
  border-bottom: 1px solid var(--border-subtle);
  background: var(--bg-elevated);
}

.inspector-tab {
  padding: 12px 18px;
  border: 0;
  border-bottom: 2px solid transparent;
  background: transparent;
  color: var(--text-secondary);
  font-family: var(--font-sans);
  font-size: 13.5px;
  font-weight: 600;
  cursor: pointer;
}

.inspector-tab[aria-selected="true"] {
  color: var(--text-primary);
  background: var(--bg-surface);
  border-bottom-color: var(--accent-blue);
}

.inspector-body {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
  padding: 20px;
}

.inspector-body[hidden] {
  display: none;
}

@media (min-width: 860px) {
  .inspector-body {
    grid-template-columns: 1.32fr 1fr;
  }
}

.sim-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  margin-bottom: 10px;
}

.sim-label {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 700;
  color: var(--text-muted);
  margin-right: 2px;
}

.sim-btn {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 600;
  padding: 4px 10px;
  border-radius: 6px;
  border: 1px solid var(--border-subtle);
  background: var(--bg-elevated);
  color: var(--text-secondary);
  cursor: pointer;
}

.sim-btn:hover {
  border-color: var(--border-strong);
  color: var(--text-primary);
}

.sim-btn.is-active {
  background: var(--accent-primary);
  color: var(--accent-primary-fg);
  border-color: var(--accent-primary);
}

.sim-status {
  padding: 9px 12px;
  border-radius: 8px;
  font-size: 12.5px;
  margin-bottom: 12px;
  border: 1px solid var(--border-subtle);
}

.sim-status.is-ok {
  background: var(--accent-green-bg);
  border-color: var(--accent-green-border);
  color: var(--accent-green);
}

.sim-status.is-fail {
  background: var(--accent-red-bg);
  border-color: var(--accent-red-border);
  color: var(--accent-red);
}

.token-strip {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 2px;
  padding: 12px 14px;
  background: var(--bg-code);
  border: 1px solid var(--border-subtle);
  border-radius: 8px;
  margin-bottom: 12px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  word-break: break-all;
}

.token-seg {
  border: 1px solid transparent;
  background: transparent;
  font-family: inherit;
  font-size: inherit;
  padding: 2px 5px;
  border-radius: 4px;
  cursor: pointer;
  text-align: left;
  word-break: break-all;
}

.token-scheme { color: var(--accent-green); font-weight: 700; }
.token-payload { color: var(--accent-blue); }
.token-sig { color: var(--accent-violet); }

.token-seg.is-active,
.token-seg:hover {
  background: var(--bg-surface);
  border-color: var(--border-strong);
}

.token-dot {
  color: var(--text-muted);
  font-weight: 700;
}

.code-json {
  margin: 0;
  padding: 14px;
  background: var(--bg-code);
  border: 1px solid var(--border-subtle);
  border-radius: 8px;
  font-size: 13px;
  line-height: 1.6;
  overflow-x: auto;
}

.json-field {
  border: 1px solid transparent;
  background: transparent;
  color: var(--text-primary);
  font-family: var(--font-mono);
  font-size: inherit;
  padding: 1px 5px;
  border-radius: 4px;
  cursor: pointer;
  text-align: left;
}

.json-field:hover,
.json-field.is-active {
  background: var(--accent-blue-bg);
  border-color: var(--accent-blue-border);
  color: var(--accent-blue);
}

.json-field.is-error {
  background: var(--accent-red-bg);
  border-color: var(--accent-red-border);
  color: var(--accent-red);
  font-weight: 600;
}

.inspector-explain-col {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 16px;
}

.explain-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: 10px;
  padding: 16px;
}

.explain-kicker {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent-blue);
  margin-bottom: 6px;
}

.explain-title {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 15px;
}

.explain-text {
  margin: 0;
  font-size: 14px;
  color: var(--text-secondary);
}

.field-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.field-chip {
  font-family: var(--font-mono);
  font-size: 12px;
  padding: 5px 10px;
  border-radius: 6px;
  border: 1px solid var(--border-subtle);
  background: var(--bg-surface);
  color: var(--text-secondary);
  cursor: pointer;
}

.field-chip.is-active {
  background: var(--accent-blue-bg);
  border-color: var(--accent-blue-border);
  color: var(--accent-blue);
  font-weight: 600;
}

/* Section 4: 5-Step Setup */
.setup-shell {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

@media (min-width: 860px) {
  .setup-shell {
    grid-template-columns: 280px 1fr;
    align-items: start;
  }
}

.setup-steps {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.setup-step-btn {
  display: flex;
  align-items: center;
  gap: 10px;
  width: 100%;
  padding: 11px 14px;
  border: 1px solid var(--border-subtle);
  border-radius: 9px;
  background: var(--bg-surface);
  color: var(--text-secondary);
  font-family: var(--font-sans);
  font-size: 13.5px;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
}

.setup-step-btn:hover {
  border-color: var(--border-strong);
  color: var(--text-primary);
}

.setup-step-btn[aria-selected="true"] {
  border-color: var(--accent-blue-border);
  background: var(--accent-blue-bg);
  color: var(--text-primary);
}

.step-num {
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--accent-blue);
}

.setup-panel {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
  padding: 20px;
  box-shadow: var(--shadow-sm);
}

.setup-panel[hidden] {
  display: none;
}

.setup-panel-head h3 {
  margin: 0 0 6px;
  font-size: 17px;
}

.setup-panel-head p {
  margin: 0 0 16px;
  font-size: 14px;
  color: var(--text-secondary);
}

.setup-panel-foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-top: 14px;
}

.setup-done-note {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--accent-green);
  font-weight: 600;
}

.code-block {
  border: 1px solid var(--border-subtle);
  border-radius: 9px;
  overflow: hidden;
  background: var(--bg-code);
}

.code-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 12px;
  border-bottom: 1px solid var(--border-subtle);
  background: var(--bg-elevated);
}

.code-lang {
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--text-muted);
}

.copy-btn {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 600;
  padding: 4px 10px;
  border-radius: 5px;
  border: 1px solid var(--border-subtle);
  background: var(--bg-surface);
  color: var(--text-primary);
  cursor: pointer;
}

.copy-btn:hover {
  border-color: var(--border-strong);
}

.copy-btn.is-copied {
  border-color: var(--accent-green-border);
  background: var(--accent-green-bg);
  color: var(--accent-green);
}

.code-block pre {
  margin: 0;
  padding: 14px;
  font-size: 13px;
  line-height: 1.55;
  overflow-x: auto;
}

/* Section 5: Security & Privacy Matrix */
.matrix-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

@media (min-width: 860px) {
  .matrix-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.matrix-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
  padding: 20px;
  box-shadow: var(--shadow-sm);
}

.matrix-title {
  margin: 0 0 12px;
  font-size: 16px;
  font-weight: 700;
}

.matrix-list {
  margin: 0;
  padding-left: 18px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 13.5px;
  color: var(--text-secondary);
}

.matrix-list code {
  font-size: 12px;
  background: var(--bg-elevated);
  padding: 1px 5px;
  border-radius: 4px;
  color: var(--text-primary);
}

/* Footer */
.site-footer {
  padding: 28px 0 40px;
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.footer-note {
  margin: 0;
  font-size: 13.5px;
  color: var(--text-secondary);
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 13.5px;
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  .svg-node,
  .svg-zone,
  .svg-edge,
  .mobile-zone,
  .mobile-node,
  .mobile-connector,
  .step-card {
    transition: none;
  }
  .arch-svg.is-pulsing .svg-edge:not(.is-dimmed) .edge-pulse {
    animation: none;
    opacity: 0;
  }
}

.code-comment {
  color: var(--text-muted, #8a8f98);
  font-style: italic;
}

.code-json .json-field {
  word-break: break-all;
}