.page-layout {
  display: grid;
  grid-template-columns: max-content minmax(0, 1fr);
  gap: 3rem;
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 2rem;
}

.page-layout:has(.topic-index__details:not([open])) {
  gap: 1rem;
}

.topic-index {
  position: sticky;
  top: 1.5rem;
  align-self: start;
  max-width: 15rem;
}

.topic-index__details {
  width: 2.35rem;
}

.topic-index__details[open] {
  width: 15rem;
  min-width: 11rem;
}

.topic-index__summary {
  cursor: pointer;
  list-style-position: inside;
  padding: 0.35rem 0;
}

.topic-index__details:not([open]) .topic-index__summary {
  display: flex;
  align-items: center;
  min-height: 8.5rem;
  padding: 0.45rem 0.25rem;
  border-left: 4px solid var(--accent);
  writing-mode: vertical-rl;
  text-orientation: mixed;
  white-space: nowrap;
}

.topic-index ol {
  display: grid;
  gap: 0.55rem;
  margin: 0.8rem 0 0;
  padding-left: 1.2rem;
}

.topic-index a {
  color: var(--muted);
}

.topic-index__toggle-all {
  margin-top: 0.35rem;
  padding: 0;
  border: 0;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font: inherit;
  font-size: 0.76rem;
  text-decoration: underline;
}

.topic-index__section {
  position: relative;
}

.topic-index__section > a {
  display: block;
  padding-right: 1.2rem;
}

.topic-index__blocks {
  margin: 0;
  color: var(--muted);
  font-size: 0.82rem;
}

.topic-index__blocks summary {
  position: absolute;
  top: 0;
  right: 0;
  width: 1rem;
  cursor: pointer;
  list-style-position: inside;
}

.topic-index__blocks ol {
  gap: 0.3rem;
  margin-top: 0.35rem;
  padding-left: 1rem;
}

main {
  min-width: 0;
}

.topic {
  padding: 0 0 3.25rem;
  scroll-margin-top: 1.5rem;
}

.topic + .topic {
  padding-top: 2.75rem;
  border-top: 2px solid var(--strong-border);
}

.topic__header {
  margin-bottom: 1.5rem;
}

.topic__note {
  margin: 0 0 0.35rem;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 750;
  text-transform: uppercase;
}

.topic--collapsed {
  padding-bottom: 1rem;
}

.topic--collapsed + .topic--collapsed {
  padding-top: 1rem;
  border-top: 1px solid var(--border);
}

.topic__summary {
  display: flex;
  align-items: baseline;
  gap: 0.7rem;
  padding: 0.95rem 1rem;
  border-left: 4px solid var(--accent);
  background: var(--surface);
  cursor: pointer;
  font-size: 1.05rem;
  font-weight: 750;
}

.topic__summary .topic__note {
  margin: 0;
}

.topic__count {
  margin-left: auto;
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 700;
}

.topic--collapsed[open] .topic__summary {
  margin-bottom: 1rem;
  background: var(--accent-soft);
}

.topic__content {
  display: grid;
  gap: 1rem;
}
@media (max-width: 760px) {
@media (max-width: 760px) {
  .site-header {
    display: block;
    padding: 2rem 1rem 1.5rem;
  }

  h1 {
    font-size: 1.8rem;
  }

  .related-pages {
    margin-top: 1.25rem;
  }

  .page-layout {
    display: block;
    padding: 1rem;
  }

  .topic-index {
    position: static;
    margin-bottom: 2.5rem;
    padding-bottom: 1.25rem;
    border-bottom: 1px solid var(--strong-border);
  }
}