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

.manual-hero-grid {
  display: grid;
  min-height: clamp(560px, 76vh, 760px);
  grid-template-columns: minmax(0, .9fr) minmax(420px, 1.1fr);
  gap: clamp(36px, 6vw, 92px);
  align-items: center;
  padding-top: clamp(64px, 8vw, 108px);
  padding-bottom: clamp(64px, 8vw, 108px);
}

.manual-hero-copy {
  position: relative;
  z-index: 2;
}

.manual-hero-copy h1 {
  max-width: 9em;
  margin-top: 1.35rem;
}

.manual-lead {
  max-width: 38rem;
  color: var(--color-muted);
  font-size: clamp(1.05rem, 1.5vw, 1.24rem);
  line-height: 1.85;
}

.manual-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0;
  max-width: 39rem;
  margin: 2rem 0 0;
  padding: 0;
  border-top: 1px solid var(--color-line);
  border-left: 1px solid var(--color-line);
  list-style: none;
}

.manual-facts li {
  display: flex;
  min-height: 86px;
  flex-direction: column;
  justify-content: center;
  padding: .9rem 1rem;
  border-right: 1px solid var(--color-line);
  border-bottom: 1px solid var(--color-line);
}

.manual-facts strong {
  font-family: var(--font-display);
  font-size: 1.15rem;
}

.manual-facts span {
  color: var(--color-muted);
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .06em;
}

.manual-specimen {
  position: relative;
  margin: 0;
  padding: clamp(20px, 3vw, 40px);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  background: var(--color-panel);
}

.manual-specimen::before,
.manual-specimen::after {
  position: absolute;
  width: 34px;
  height: 34px;
  border-color: var(--color-accent);
  content: "";
}

.manual-specimen::before {
  top: 12px;
  left: 12px;
  border-top: 1px solid var(--color-accent);
  border-left: 1px solid var(--color-accent);
}

.manual-specimen::after {
  right: 12px;
  bottom: 42px;
  border-right: 1px solid var(--color-accent);
  border-bottom: 1px solid var(--color-accent);
}

.manual-specimen svg {
  width: 100%;
}

.manual-specimen figcaption {
  padding-top: .8rem;
  border-top: 1px solid var(--color-line);
  color: var(--color-muted);
  font-family: var(--font-mono);
  font-size: .68rem;
  letter-spacing: .08em;
}

.specimen-route {
  fill: none;
  stroke-linecap: round;
  stroke-width: 4;
}

.route-main {
  stroke: var(--color-accent);
  stroke-dasharray: 9 14;
}

.route-sky {
  stroke: var(--color-sky-deep);
  stroke-dasharray: 4 18;
}

.specimen-station {
  fill: var(--color-page);
  stroke: var(--color-accent);
  stroke-width: 3;
}

.specimen-bird {
  fill: var(--color-accent);
  stroke: var(--color-accent-dark);
  stroke-width: 3;
}

.specimen-belly {
  fill: var(--color-page);
  stroke: var(--color-accent-dark);
  stroke-width: 2;
}

.specimen-wing {
  fill: var(--color-apricot);
  stroke: var(--color-accent-dark);
  stroke-width: 3;
}

.specimen-beak {
  fill: var(--color-yellow);
  stroke: var(--color-accent-dark);
  stroke-width: 2;
}

.specimen-eye {
  fill: var(--color-ink);
}

.specimen-pack {
  fill: var(--color-sky);
  stroke: var(--color-ink);
  stroke-width: 3;
}

.specimen-lock {
  fill: var(--color-yellow);
  stroke: var(--color-ink);
  stroke-width: 3;
}

.specimen-tail {
  fill: var(--color-apricot);
  stroke: var(--color-accent-dark);
  stroke-width: 3;
}

.manual-intro {
  border-left: 4px solid var(--color-accent);
  background: var(--color-panel);
}

.manual-intro p:last-child {
  margin-bottom: 0;
}

.manual-intro a {
  color: var(--color-accent-dark);
  text-decoration: underline;
  text-underline-offset: .18em;
}

.manual-layout {
  display: grid;
  grid-template-columns: minmax(190px, 240px) minmax(0, var(--reading-max));
  gap: clamp(40px, 7vw, 100px);
  justify-content: center;
  align-items: start;
  padding-bottom: var(--space-section);
}

.manual-index {
  position: relative;
  align-self: stretch;
  padding-top: 1rem;
}

.manual-index-title {
  margin-bottom: .7rem;
  color: var(--color-accent-dark);
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .12em;
}

.manual-index .toc-tabs {
  flex-direction: column;
  align-items: stretch;
  box-shadow: none;
}

.manual-index .toc-tabs a {
  width: 100%;
  white-space: normal;
}

.manual-prose {
  min-width: 0;
}

.manual-chapter {
  padding-top: clamp(68px, 8vw, 104px);
  padding-bottom: clamp(48px, 7vw, 84px);
  border-bottom: 1px solid var(--color-line);
}

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

.chapter-mark {
  display: inline-flex;
  margin-bottom: .85rem;
  padding: .25rem .62rem;
  border: 1px solid var(--color-accent);
  border-radius: var(--radius-pill);
  color: var(--color-accent-dark);
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .1em;
}

.manual-chapter h2 {
  position: relative;
  margin-bottom: 2.2rem;
  padding-bottom: 1.1rem;
}

.manual-chapter h2::after {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 76px;
  height: 3px;
  border-radius: var(--radius-pill);
  background: var(--color-accent);
  content: "";
}

.manual-chapter h3 {
  margin-top: 2.5rem;
  font-size: clamp(22px, 2.4vw, 28px);
}

.manual-chapter p {
  line-height: 1.92;
}

.manual-chapter .table-scroll {
  margin: 2rem 0 2.5rem;
}

.manual-chapter pre {
  margin: 1.8rem 0 2.4rem;
  border: 1px solid var(--color-ink);
  border-left: 5px solid var(--color-accent);
  border-radius: var(--radius-sm);
}

.manual-chapter .callout {
  margin-top: 2.2rem;
  margin-bottom: 2.2rem;
}

@media (max-width: 1040px) {
  .manual-hero-grid {
    grid-template-columns: minmax(0, 1fr) minmax(340px, .85fr);
  }

  .manual-layout {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .manual-index {
    z-index: 45;
    padding-top: 0;
    background: var(--color-page);
  }

  .manual-index-title {
    display: none;
  }

  .manual-index .toc-tabs {
    flex-direction: row;
    align-items: center;
  }

  .manual-index .toc-tabs a {
    width: auto;
    white-space: nowrap;
  }

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

@media (max-width: 768px) {
  .manual-hero-grid {
    min-height: 0;
    grid-template-columns: 1fr;
    gap: 42px;
    padding-top: 52px;
    padding-bottom: 58px;
  }

  .manual-hero-copy h1 {
    max-width: 100%;
  }

  .manual-specimen {
    width: 100%;
    max-width: 560px;
    margin-inline: auto;
  }

  .manual-chapter {
    padding-top: 64px;
    padding-bottom: 48px;
  }

  .manual-chapter h2 {
    margin-bottom: 1.7rem;
  }

  .manual-chapter h3 {
    margin-top: 2rem;
  }
}

@media (max-width: 520px) {
  .manual-facts {
    grid-template-columns: 1fr;
  }

  .manual-facts li {
    min-height: 72px;
  }

  .manual-specimen {
    padding: 14px;
  }

  .manual-specimen figcaption {
    font-size: .61rem;
    overflow-wrap: anywhere;
  }

  .manual-chapter .callout {
    padding-right: 1rem;
  }
}