.handbook-hero {
  padding-top: clamp(44px, 7vw, 88px);
  padding-bottom: clamp(48px, 8vw, 96px);
}

.handbook-hero::before {
  position: absolute;
  z-index: -1;
  top: -24%;
  right: -18%;
  width: min(72vw, 920px);
  aspect-ratio: 1;
  border-radius: var(--radius-pill);
  background: var(--gradient-glow);
  content: "";
  pointer-events: none;
}

.handbook-hero-panel {
  display: grid;
  grid-template-columns: minmax(0, 1.55fr) minmax(260px, 0.75fr);
  gap: clamp(32px, 6vw, 76px);
  align-items: end;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-xl);
  padding: clamp(30px, 6vw, 72px);
  background: var(--color-page);
  box-shadow: var(--shadow-window);
}

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

.handbook-hero h1 {
  max-width: 760px;
  margin-top: 22px;
  font-size: clamp(34px, 3.3vw, 48px);
}

.handbook-lead {
  max-width: 720px;
  margin-bottom: 28px;
  color: var(--color-muted);
  font-size: clamp(17px, 1.5vw, 20px);
  line-height: 1.75;
}

.handbook-scope {
  display: grid;
  gap: 8px;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  padding: 24px;
  background: var(--color-panel);
  box-shadow: var(--shadow-card);
}

.handbook-scope span {
  color: var(--color-muted);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.04em;
}

.handbook-scope strong {
  margin-bottom: 12px;
  font-size: 14px;
  line-height: 1.6;
}

.handbook-scope strong:last-child {
  margin-bottom: 0;
}

.handbook-document {
  padding-top: clamp(42px, 6vw, 76px);
  padding-bottom: var(--section-space);
}

.handbook-document .toc {
  top: 12px;
}

.handbook-article {
  width: 100%;
  max-width: var(--reading-width);
  margin-inline: auto;
}

.handbook-chapter {
  scroll-margin-top: calc(var(--header-height) + 76px);
  padding-top: clamp(44px, 7vw, 78px);
  padding-bottom: clamp(44px, 7vw, 78px);
  border-bottom: 1px solid var(--color-line);
}

.handbook-chapter:first-child {
  padding-top: 24px;
}

.handbook-chapter:last-child {
  border-bottom: 0;
}

.chapter-heading {
  display: grid;
  grid-template-columns: 54px minmax(0, 1fr);
  gap: 18px;
  align-items: start;
  margin-bottom: 30px;
}

.chapter-index {
  display: inline-flex;
  width: 54px;
  height: 54px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  background: var(--color-panel);
  color: var(--color-brand-deep);
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 800;
  box-shadow: var(--shadow-card);
}

.chapter-kicker {
  margin-bottom: 4px;
  color: var(--color-brand-deep);
  font-size: 13px;
  font-weight: 750;
  letter-spacing: 0.08em;
}

.chapter-heading h2 {
  margin-bottom: 0;
}

.handbook-chapter h3 {
  margin-top: 2.15em;
  padding-top: 0.2em;
  font-size: clamp(21px, 2.3vw, 27px);
}

.handbook-chapter p,
.handbook-chapter li {
  line-height: 1.86;
}

.handbook-chapter .table-wrap {
  margin-top: 28px;
  margin-bottom: 32px;
  box-shadow: var(--shadow-card);
}

.handbook-chapter th {
  white-space: nowrap;
}

.handbook-chapter pre {
  margin-top: 24px;
  margin-bottom: 28px;
}

.handbook-chapter .callout {
  margin-top: 30px;
  margin-bottom: 34px;
}

@media (max-width: 860px) {
  .handbook-hero-panel {
    grid-template-columns: minmax(0, 1fr);
    align-items: start;
  }

  .handbook-scope {
    grid-template-columns: minmax(90px, 0.38fr) minmax(0, 1fr);
    align-items: baseline;
  }

  .handbook-scope strong {
    margin-bottom: 0;
  }

  .handbook-document .toc {
    top: 8px;
  }
}

@media (max-width: 640px) {
  .handbook-hero {
    padding-top: 28px;
    padding-bottom: 46px;
  }

  .handbook-hero-panel {
    gap: 26px;
    padding: 25px 18px;
  }

  .handbook-hero h1 {
    font-size: clamp(25px, 7.5vw, 30px);
  }

  .handbook-lead {
    font-size: 16px;
  }

  .handbook-scope {
    grid-template-columns: minmax(0, 1fr);
    gap: 5px;
    padding: 20px;
  }

  .handbook-scope strong {
    margin-bottom: 12px;
  }

  .handbook-scope strong:last-child {
    margin-bottom: 0;
  }

  .handbook-document {
    padding-top: 32px;
  }

  .chapter-heading {
    grid-template-columns: 42px minmax(0, 1fr);
    gap: 13px;
  }

  .chapter-index {
    width: 42px;
    height: 42px;
    font-size: 12px;
  }

  .chapter-heading h2 {
    font-size: clamp(25px, 7.6vw, 32px);
  }

  .handbook-chapter h3 {
    font-size: 21px;
  }
}