.ai-hero {
  position: relative;
  overflow-x: clip;
  border-bottom: 1px solid var(--color-border);
}

.ai-hero::before {
  position: absolute;
  top: 8%;
  right: 4%;
  width: min(48vw, 680px);
  height: min(48vw, 680px);
  border-radius: var(--radius-pill);
  background: radial-gradient(circle, var(--color-panel-deep), transparent 70%);
  content: "";
  pointer-events: none;
}

.ai-hero-inner {
  position: relative;
  min-height: calc(100svh - var(--header-height));
  padding-top: clamp(62px, 9vw, 118px);
  padding-bottom: clamp(62px, 9vw, 118px);
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(420px, 1.08fr);
  align-items: center;
  gap: clamp(38px, 6vw, 84px);
}

.ai-hero-copy {
  min-width: 0;
}

.ai-hero-copy h1 {
  max-width: 720px;
  margin-top: 18px;
  font-size: clamp(48px, 5.3vw, 68px);
}

.ai-hero-copy .lead {
  max-width: 690px;
}

.ai-hero-copy .hero-actions {
  justify-content: flex-start;
}

.ai-trust-list {
  margin-top: 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  color: var(--color-text-soft);
  font-size: 13px;
}

.ai-trust-list span {
  display: inline-flex;
  align-items: center;
}

.ai-trust-list span + span::before {
  padding-right: 18px;
  color: var(--color-border);
  content: "·";
  font-weight: 800;
}

.ai-signal-panel {
  min-width: 0;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-large);
  background: var(--color-panel);
  box-shadow: var(--shadow-card);
}

.ai-signal-head {
  min-height: 48px;
  padding: 0 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--color-border);
  background: var(--color-panel-deep);
  color: var(--color-text-soft);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
}

.ai-signal-panel svg {
  width: 100%;
  height: auto;
}

.ai-path-main,
.ai-path-backup {
  fill: none;
  stroke: var(--color-accent);
  stroke-linecap: round;
}

.ai-path-main {
  stroke-width: 4;
}

.ai-path-backup {
  stroke-width: 3;
  stroke-dasharray: 3 11;
  opacity: 0.38;
}

.ai-path-halo {
  fill: var(--color-accent);
  opacity: 0.13;
  transform-box: fill-box;
  transform-origin: center;
  animation: ai-node-pulse 3.4s ease-in-out infinite;
}

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

.ai-path-node-soft {
  opacity: 0.55;
}

.ai-svg-label,
.ai-svg-note {
  fill: var(--color-text-soft);
}

.ai-svg-label {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.ai-svg-note {
  font-family: var(--font-body);
  font-size: 13px;
}

@keyframes ai-node-pulse {
  50% {
    opacity: 0.04;
    transform: scale(1.42);
  }
}

.ai-toc-wrap {
  position: relative;
  z-index: 46;
  margin-top: 28px;
}

.ai-toc-wrap .toc-tabs {
  top: 12px;
}

.ai-article {
  min-width: 0;
}

.section-ai-deep {
  background: var(--color-panel-deep);
}

.ai-requirement-layout {
  display: grid;
  grid-template-columns: minmax(210px, 0.58fr) minmax(0, 1.62fr);
  gap: 22px;
}

.ai-requirement-index {
  padding: 8px;
  display: grid;
  align-content: start;
  gap: 6px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-large);
  background: var(--color-panel);
}

.ai-requirement-index span {
  min-height: 50px;
  padding: 11px 16px;
  display: flex;
  align-items: center;
  border-radius: var(--radius-pill);
  color: var(--color-text-soft);
  font-weight: 700;
}

.ai-requirement-index .is-active {
  background: var(--color-panel-deep);
  color: var(--color-accent-deep);
}

.ai-requirement-copy {
  padding: clamp(26px, 4vw, 46px);
  box-shadow: var(--shadow-card);
}

.ai-requirement-copy p {
  color: var(--color-text-soft);
}

.ai-requirement-copy .callout {
  margin-top: 26px;
}

.ai-tool-notes {
  margin-top: 24px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  perspective: 1000px;
}

.ai-note {
  min-width: 0;
  padding: 24px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-large);
  background: var(--color-panel);
  box-shadow: var(--shadow-card);
  transform-style: preserve-3d;
  will-change: transform;
}

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

.ai-note p {
  color: var(--color-text-soft);
  font-size: 14px;
}

.ai-reading-grid {
  display: grid;
  grid-template-columns: minmax(240px, 0.72fr) minmax(0, 1.28fr);
  gap: clamp(32px, 7vw, 90px);
}

.ai-reading-title {
  align-self: start;
}

.ai-reading-title h2 {
  position: sticky;
  top: var(--toc-offset);
}

.ai-reading-copy {
  min-width: 0;
}

.ai-reading-copy p {
  font-size: 17px;
  line-height: 1.85;
}

.ai-reading-copy .callout {
  margin-top: 28px;
}

.ai-flow {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.ai-flow-step {
  min-width: 0;
  padding: 26px;
  border-top: 3px solid var(--color-accent);
  border-right: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  border-left: 1px solid var(--color-border);
  border-radius: var(--radius-medium);
  background: var(--color-panel);
}

.ai-flow-mark {
  margin-bottom: 22px;
  display: inline-flex;
  min-height: 28px;
  align-items: center;
  padding: 4px 11px;
  border-radius: var(--radius-pill);
  background: var(--color-panel-deep);
  color: var(--color-accent-deep);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.08em;
}

.ai-flow-step h3 {
  font-size: 21px;
}

.ai-flow-step p {
  color: var(--color-text-soft);
  font-size: 14px;
}

.ai-wide-callout {
  margin-top: 24px;
}

.ai-dev-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.ai-dev-panel {
  min-width: 0;
  padding: 28px;
}

.ai-dev-panel h3 {
  font-size: 21px;
}

.ai-dev-panel p,
.ai-dev-panel li {
  color: var(--color-text-soft);
}

.ai-dev-panel ul {
  margin-bottom: 0;
  padding-left: 20px;
}

.ai-dev-panel li + li {
  margin-top: 8px;
}

.ai-failure-list {
  max-width: 900px;
}

.ai-help-link {
  max-width: 900px;
  margin-top: 26px;
  color: var(--color-text-soft);
}

.ai-help-link a,
.ai-selection-copy a {
  color: var(--color-accent-deep);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.ai-selection-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(300px, 0.65fr);
  align-items: start;
  gap: clamp(26px, 5vw, 64px);
}

.ai-selection-copy h3:first-child {
  margin-top: 0;
}

.ai-plan-panel {
  position: sticky;
  top: var(--toc-offset);
  padding: 28px;
  box-shadow: var(--shadow-card);
}

.ai-plan-panel h3 {
  margin-top: 20px;
}

.ai-plan-panel dl {
  margin: 22px 0;
}

.ai-plan-panel dl div {
  padding: 14px 0;
  display: grid;
  grid-template-columns: minmax(0, 0.65fr) minmax(0, 1.35fr);
  gap: 16px;
  border-bottom: 1px solid var(--color-border);
}

.ai-plan-panel dt {
  color: var(--color-text-soft);
}

.ai-plan-panel dd {
  margin: 0;
  color: var(--color-accent-deep);
  font-family: var(--font-mono);
  font-weight: 800;
  text-align: right;
}

.ai-plan-panel p {
  color: var(--color-text-soft);
  font-size: 14px;
}

.ai-plan-panel .btn-secondary {
  width: 100%;
  margin-top: 10px;
}

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

  .ai-hero-copy {
    max-width: 760px;
  }

  .ai-signal-panel {
    max-width: 760px;
  }

  .ai-tool-notes,
  .ai-flow,
  .ai-dev-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .ai-plan-panel {
    position: static;
  }
}

@media (max-width: 768px) {
  .ai-hero-inner {
    padding-top: 54px;
    padding-bottom: 62px;
  }

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

  .ai-trust-list span + span::before {
    padding-right: 10px;
  }

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

  .ai-requirement-index {
    display: flex;
    overflow-x: auto;
    overscroll-behavior-inline: contain;
  }

  .ai-requirement-index span {
    min-width: max-content;
  }

  .ai-reading-title h2 {
    position: static;
  }

  .ai-tool-notes,
  .ai-flow,
  .ai-dev-grid {
    grid-template-columns: minmax(0, 1fr);
  }
}

@media (max-width: 640px) {
  .ai-signal-panel svg {
    width: 560px;
    max-width: none;
  }

  .ai-signal-panel {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }

  .ai-trust-list {
    display: grid;
    gap: 7px;
  }

  .ai-trust-list span + span::before {
    display: none;
  }

  .ai-requirement-copy,
  .ai-dev-panel,
  .ai-plan-panel {
    padding: 22px;
  }

  .ai-plan-panel dl div {
    grid-template-columns: minmax(0, 1fr);
    gap: 4px;
  }

  .ai-plan-panel dd {
    text-align: left;
  }
}

@media (prefers-reduced-motion: reduce) {
  .ai-path-halo {
    animation: none;
  }
}