.ai-hero {
  border-bottom: 1px solid var(--color-line);
}

.ai-context {
  background: var(--color-surface);
}

.ai-context-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
  gap: 1px;
  overflow: hidden;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-medium);
  background: var(--color-line);
}

.ai-principle {
  position: relative;
  min-height: 100%;
  padding: clamp(30px, 5vw, 56px);
  background: var(--color-canvas);
}

.ai-principle-primary {
  grid-row: span 2;
  background: linear-gradient(145deg, var(--color-encode-teal), var(--color-encode-amber));
}

.ai-principle-primary h3,
.ai-principle-primary p,
.ai-principle-primary .ai-rail-label {
  color: var(--color-white);
}

.ai-principle h3 {
  max-width: 16em;
  font-family: var(--font-display);
  font-size: clamp(28px, 3vw, 40px);
  font-weight: 400;
}

.ai-principle p {
  color: var(--color-ink-soft);
}

.ai-principle p:last-child {
  margin-bottom: 0;
}

.ai-principle-primary p {
  color: var(--color-white);
}

.ai-rail-label {
  margin-bottom: 28px;
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 650;
  letter-spacing: 0.14em;
}

.ai-matrix-section {
  border-bottom: 1px solid var(--color-line);
}

.ai-tool-table th:nth-child(1) {
  min-width: 130px;
}

.ai-tool-table th:nth-child(2),
.ai-tool-table th:nth-child(3),
.ai-tool-table th:nth-child(4),
.ai-tool-table th:nth-child(5) {
  min-width: 210px;
}

.ai-table-note {
  margin-bottom: 0;
}

.ai-scenarios {
  background: var(--color-surface);
}

.ai-scenario-layout {
  display: grid;
  grid-template-columns: minmax(190px, 0.34fr) minmax(0, 1fr);
  gap: clamp(34px, 6vw, 88px);
  align-items: start;
}

.ai-scenario-index {
  position: sticky;
  top: var(--toc-offset);
  display: grid;
  border-top: 1px solid var(--color-line);
}

.ai-scenario-index span {
  padding: 16px 0;
  border-bottom: 1px solid var(--color-line);
  color: var(--color-ink-soft);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
}

.ai-scenario-index span.is-current {
  color: var(--color-accent);
  font-weight: 700;
}

.ai-scenario-content {
  counter-reset: scenario;
}

.ai-scenario-content article {
  position: relative;
  padding: 0 0 clamp(42px, 6vw, 76px) 48px;
  counter-increment: scenario;
}

.ai-scenario-content article:not(:last-child) {
  margin-bottom: clamp(34px, 5vw, 64px);
  border-bottom: 1px solid var(--color-line);
}

.ai-scenario-content article::before {
  position: absolute;
  top: 3px;
  left: 0;
  display: grid;
  width: 30px;
  height: 30px;
  place-items: center;
  border: 1px solid var(--color-accent);
  border-radius: var(--radius-pill);
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: 11px;
  content: counter(scenario, decimal-leading-zero);
}

.ai-scenario-content article:last-child {
  padding-bottom: 0;
}

.ai-scenario-content h3 {
  font-family: var(--font-display);
  font-size: clamp(28px, 3vw, 38px);
  font-weight: 400;
}

.ai-scenario-content p {
  max-width: 48em;
  color: var(--color-ink-soft);
  font-size: 16px;
}

.ai-code-caption {
  margin-top: -10px;
  font-family: var(--font-mono);
  font-size: 11px !important;
}

.ai-diagnostic-list {
  border-top: 1px solid var(--color-line);
}

.ai-diagnostic {
  display: grid;
  grid-template-columns: 120px minmax(0, 1fr);
  gap: clamp(24px, 5vw, 72px);
  padding-top: 34px;
  padding-bottom: 34px;
  border-bottom: 1px solid var(--color-line);
}

.ai-diagnostic-mark {
  padding-top: 6px;
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.12em;
}

.ai-diagnostic h3 {
  font-family: var(--font-display);
  font-size: clamp(25px, 3vw, 34px);
  font-weight: 400;
}

.ai-diagnostic p {
  max-width: 54em;
  margin-bottom: 0;
  color: var(--color-ink-soft);
}

.ai-selection {
  padding-top: clamp(40px, 6vw, 80px);
}

.ai-selection-panel {
  display: grid;
  grid-template-columns: minmax(0, 1.45fr) minmax(260px, 0.55fr);
  gap: clamp(36px, 6vw, 86px);
  align-items: center;
  overflow: hidden;
  padding: clamp(34px, 6vw, 72px);
  border-radius: var(--radius-large);
  background: linear-gradient(120deg, var(--color-encode-teal), var(--color-encode-amber));
}

.ai-selection-copy h2,
.ai-selection-copy p,
.ai-selection-copy .section-kicker {
  color: var(--color-white);
}

.ai-selection-copy .section-kicker::before {
  background: var(--color-white);
}

.ai-selection-copy p {
  max-width: 52em;
}

.ai-selection-copy .button-row {
  margin-top: 28px;
}

.ai-selection-copy .button {
  background: var(--color-white);
  color: var(--color-ink);
}

.ai-selection-copy .button:hover {
  color: var(--color-ink);
}

.ai-selection-copy .btn-sub {
  border-color: var(--color-white);
  color: var(--color-white);
}

.ai-selection-copy .btn-sub:hover {
  border-color: var(--color-white);
  color: var(--color-white);
  opacity: 0.82;
}

.ai-selection-checklist {
  padding: 28px;
  border: 1px solid var(--color-hair-white);
  border-radius: var(--radius-medium);
  background: var(--color-code-white);
}

.ai-selection-checklist h3 {
  font-family: var(--font-display);
  font-weight: 400;
}

.ai-selection-checklist ul {
  margin-bottom: 0;
  padding-left: 0;
  list-style: none;
}

.ai-selection-checklist li {
  position: relative;
  padding-left: 20px;
  color: var(--color-ink);
  font-size: 14px;
}

.ai-selection-checklist li::before {
  position: absolute;
  top: 0.67em;
  left: 0;
  width: 7px;
  height: 7px;
  border-radius: var(--radius-pill);
  background: var(--color-success);
  content: "";
}

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

  .ai-principle-primary {
    grid-row: auto;
  }

  .ai-scenario-layout {
    grid-template-columns: 1fr;
  }

  .ai-scenario-index {
    position: static;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    border: 1px solid var(--color-line);
    border-radius: var(--radius-small);
    background: var(--color-canvas);
  }

  .ai-scenario-index span {
    padding: 14px;
    border-bottom: 1px solid var(--color-line);
  }

  .ai-selection-panel {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 700px) {
  .ai-scenario-index {
    grid-template-columns: 1fr;
  }

  .ai-scenario-content article {
    padding-left: 42px;
  }

  .ai-diagnostic {
    grid-template-columns: 1fr;
    gap: 10px;
  }

  .ai-diagnostic-mark {
    padding-top: 0;
  }

  .ai-selection-panel {
    padding: 28px 20px;
  }

  .ai-selection-checklist {
    padding: 22px;
  }
}

@media (max-width: 420px) {
  .ai-principle {
    padding: 26px 20px;
  }

  .ai-scenario-content article {
    padding-left: 0;
    padding-top: 46px;
  }

  .ai-scenario-content article::before {
    top: 0;
  }
}