.ai-hero {
  position: relative;
  min-height: calc(100vh - var(--header-height));
  padding-top: clamp(68px, 9vw, 126px);
  padding-bottom: clamp(76px, 10vw, 138px);
  overflow: hidden;
  border-bottom: 6px solid var(--color-border);
  background:
    linear-gradient(to bottom, var(--color-bg), var(--color-bg-panel));
}

.ai-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--color-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--color-grid) 1px, transparent 1px);
  background-size: 88px 88px;
  opacity: 0.44;
  pointer-events: none;
}

.ai-hero::after {
  content: "";
  width: 42%;
  height: 5px;
  position: absolute;
  bottom: 0;
  left: 0;
  background: var(--color-accent);
}

.ai-hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1.08fr) minmax(380px, 0.92fr);
  align-items: center;
  gap: clamp(36px, 6vw, 92px);
}

.ai-hero-grid > * {
  min-width: 0;
}

.ai-hero-copy h1 {
  max-width: 760px;
  margin-bottom: 24px;
  font-size: clamp(52px, 6vw, 72px);
}

.ai-hero-copy h1::after {
  content: "";
  width: min(280px, 52%);
  height: 5px;
  margin-top: 18px;
  display: block;
  background: var(--color-accent);
}

.ai-hero-lead {
  max-width: 720px;
  margin: 26px 0 0;
  color: var(--color-text-muted);
  font-size: clamp(17px, 1.8vw, 21px);
  line-height: 1.8;
}

.ai-fact-band {
  margin-top: 30px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  border-top: 3px solid var(--color-border);
  border-left: 1px solid var(--color-border);
  background: var(--color-panel-glass);
}

.ai-fact-band span {
  min-width: 0;
  padding: 14px 16px;
  border-right: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-size: 13px;
}

.ai-fact-band strong {
  margin-right: 8px;
  color: var(--color-text);
  font-family: var(--font-mono);
  font-weight: 720;
}

.ai-route-visual {
  min-height: 480px;
  display: grid;
  place-items: center;
  border-top: 5px solid var(--color-border);
  border-right: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  border-left: 1px solid var(--color-border);
  background: var(--color-panel-glass);
  box-shadow: var(--shadow-panel);
}

.ai-route-visual svg {
  width: 100%;
  height: auto;
}

.ai-orbit,
.ai-spoke {
  fill: none;
  stroke: var(--color-border);
  stroke-width: 1.5;
}

.ai-orbit-secondary {
  stroke-dasharray: 5 10;
}

.ai-route-line {
  fill: none;
  stroke: var(--color-accent);
  stroke-width: 4;
  stroke-linecap: square;
}

.ai-route-return {
  stroke-width: 2;
  stroke-dasharray: 6 9;
}

.ai-node-ring {
  fill: var(--color-bg-panel);
  stroke: var(--color-text);
  stroke-width: 2;
}

.ai-node-core {
  fill: var(--color-accent);
}

.ai-tool-node {
  fill: var(--color-bg-panel-2);
  stroke: var(--color-text-muted);
  stroke-width: 1.5;
}

.ai-map-label,
.ai-map-caption {
  fill: var(--color-text);
  font-family: var(--font-mono);
  letter-spacing: 0.12em;
}

.ai-map-label {
  font-size: 13px;
}

.ai-map-caption {
  fill: var(--color-text-muted);
  font-size: 10px;
}

.ai-requirement-layout {
  display: grid;
  grid-template-columns: minmax(220px, 0.34fr) minmax(0, 1fr);
  gap: clamp(34px, 7vw, 96px);
}

.ai-requirement-layout > * {
  min-width: 0;
}

.ai-side-note {
  align-self: start;
  position: sticky;
  top: var(--toc-top);
  padding-top: 22px;
  border-top: 5px solid var(--color-accent);
  color: var(--color-text-muted);
}

.ai-principle-stack {
  border-top: 5px solid var(--color-border);
}

.ai-principle {
  padding-top: clamp(28px, 4vw, 48px);
  padding-bottom: clamp(28px, 4vw, 48px);
  border-bottom: 1px solid var(--color-border);
}

.ai-principle:nth-child(even) {
  padding-left: clamp(0px, 7vw, 92px);
}

.ai-principle p {
  max-width: 780px;
  margin-bottom: 0;
  color: var(--color-text-muted);
}

.ai-tool-table td {
  min-width: 180px;
}

.ai-tool-table td:first-child {
  min-width: 140px;
  color: var(--color-text);
}

.ai-tool-table tbody tr:nth-child(even) {
  background: var(--color-bg-panel-2);
}

.ai-channel-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.ai-channel {
  min-width: 0;
  padding: clamp(26px, 4vw, 42px);
  border-top: 6px solid var(--color-border);
  border-right: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  border-left: 1px solid var(--color-border);
  background: var(--color-bg-panel);
}

.ai-channel:nth-child(even) {
  border-top-color: var(--color-accent);
  background: var(--color-bg-panel-2);
}

.ai-channel p:not(.entry-number) {
  color: var(--color-text-muted);
}

.ai-channel > :last-child {
  margin-bottom: 0;
}

.ai-boundary-list {
  margin-top: 18px;
  border-top: 4px solid var(--color-border);
  background: var(--color-bg-panel);
}

.ai-boundary-list section {
  padding: 24px;
  display: grid;
  grid-template-columns: minmax(220px, 0.34fr) minmax(0, 1fr);
  gap: 28px;
  border-right: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  border-left: 1px solid var(--color-border);
}

.ai-boundary-list h3,
.ai-boundary-list p {
  margin-bottom: 0;
}

.ai-boundary-list h3 {
  font-size: 20px;
}

.ai-boundary-list p {
  color: var(--color-text-muted);
}

.ai-workflow {
  border-top: 5px solid var(--color-border);
}

.ai-workflow-row {
  padding-top: clamp(28px, 4vw, 46px);
  padding-bottom: clamp(28px, 4vw, 46px);
  display: grid;
  grid-template-columns: minmax(150px, 0.24fr) minmax(0, 1fr);
  gap: clamp(24px, 5vw, 70px);
  border-bottom: 1px solid var(--color-border);
}

.ai-workflow-row > * {
  min-width: 0;
}

.ai-workflow-row:nth-child(even) {
  background: var(--color-bg-panel);
}

.ai-workflow-row:nth-child(even) > * {
  padding-right: clamp(18px, 3vw, 38px);
}

.ai-workflow-row:nth-child(even) .ai-workflow-label {
  padding-left: clamp(18px, 3vw, 38px);
}

.ai-workflow-row p {
  max-width: 820px;
  margin-bottom: 0;
  color: var(--color-text-muted);
}

.ai-workflow-label {
  align-self: start;
}

.ai-failure-list {
  border-top: 4px solid var(--color-border);
}

.ai-selection-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 16px;
}

.ai-selection-panel {
  min-width: 0;
  grid-column: span 7;
  padding: clamp(24px, 4vw, 40px);
  border-top: 5px solid var(--color-border);
  border-right: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  border-left: 1px solid var(--color-border);
  background: var(--color-bg-panel);
}

.ai-selection-panel:nth-child(even) {
  grid-column: span 5;
  background: var(--color-bg-panel-2);
}

.ai-selection-panel:nth-child(3) {
  grid-column: span 5;
}

.ai-selection-panel:nth-child(4) {
  grid-column: span 7;
  border-top-color: var(--color-accent);
}

.ai-selection-panel p:last-child {
  margin-bottom: 0;
  color: var(--color-text-muted);
}

.ai-next-links {
  margin-top: 22px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  border-top: 5px solid var(--color-border);
  border-left: 1px solid var(--color-border);
}

.ai-next-link {
  min-width: 0;
  padding: 26px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 8px 18px;
  border-right: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  background: var(--color-bg-panel);
  transition:
    background-color var(--transition-fast),
    border-color var(--transition-fast);
}

.ai-next-link:hover,
.ai-next-link:focus-visible {
  background: var(--color-bg-panel-2);
  border-bottom-color: var(--color-accent);
}

.ai-next-link .entry-number,
.ai-next-link strong,
.ai-next-link > span:nth-child(3) {
  grid-column: 1;
}

.ai-next-link .entry-number {
  margin-bottom: 2px;
}

.ai-next-link strong {
  font-size: 21px;
}

.ai-next-link > span:nth-child(3) {
  color: var(--color-text-muted);
  font-size: 14px;
}

.ai-next-link .button-arrow {
  grid-column: 2;
  grid-row: 1 / span 3;
  align-self: center;
  color: var(--color-accent);
  font-size: 24px;
}

@media (max-width: 980px) {
  .ai-hero-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .ai-route-visual {
    min-height: 400px;
  }

  .ai-selection-panel,
  .ai-selection-panel:nth-child(even),
  .ai-selection-panel:nth-child(3),
  .ai-selection-panel:nth-child(4) {
    grid-column: span 6;
  }
}

@media (max-width: 760px) {
  .ai-hero {
    min-height: auto;
    padding-top: 58px;
    padding-bottom: 72px;
  }

  .ai-hero-grid {
    gap: 42px;
  }

  .ai-hero-copy h1 {
    font-size: clamp(32px, 9vw, 40px);
  }

  .ai-route-visual {
    min-height: 0;
  }

  .ai-requirement-layout {
    grid-template-columns: minmax(0, 1fr);
  }

  .ai-side-note {
    position: static;
  }

  .ai-principle:nth-child(even) {
    padding-left: 0;
  }

  .ai-channel-grid,
  .ai-next-links {
    grid-template-columns: minmax(0, 1fr);
  }

  .ai-boundary-list section,
  .ai-workflow-row {
    grid-template-columns: minmax(0, 1fr);
  }

  .ai-workflow-row:nth-child(even) > *,
  .ai-workflow-row:nth-child(even) .ai-workflow-label {
    padding-right: 18px;
    padding-left: 18px;
  }

  .ai-selection-panel,
  .ai-selection-panel:nth-child(even),
  .ai-selection-panel:nth-child(3),
  .ai-selection-panel:nth-child(4) {
    grid-column: 1 / -1;
  }
}

@media (max-width: 520px) {
  .ai-fact-band {
    grid-template-columns: minmax(0, 1fr);
  }

  .ai-route-visual {
    box-shadow: none;
  }

  .ai-boundary-list section {
    padding: 20px 16px;
  }

  .ai-selection-panel,
  .ai-channel,
  .ai-next-link {
    padding: 22px 18px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .ai-next-link {
    transition: none;
  }
}