/* Sidebar: clearer section vs page hierarchy (desktop primary nav). */

/* More space between top-level sections */
.md-nav--primary > .md-nav__list > .md-nav__item--section:not(:first-child) {
  margin-top: 0.65rem;
  padding-top: 0.65rem;
  border-top: 1px solid var(--md-default-fg-color--lightest);
}

/* Section headers (Concepts, Install, …) */
.md-nav--primary > .md-nav__list > .md-nav__item--section > .md-nav__link {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--md-default-fg-color--light);
  margin-bottom: 0.15rem;
}

/* Nested pages: slightly smaller, indented */
.md-nav--primary .md-nav__item--nested > .md-nav > .md-nav__list > .md-nav__item > .md-nav__link {
  font-size: 0.8125rem;
  padding-left: 0.35rem;
}

/* Deeper nesting (e.g. Operations → Engines) */
.md-nav--primary .md-nav__item--nested .md-nav__item--nested > .md-nav > .md-nav__list > .md-nav__item > .md-nav__link {
  padding-left: 0.85rem;
  font-size: 0.8rem;
}

/* Active trail: keep current section readable */
.md-nav--primary .md-nav__link--active {
  font-weight: 600;
}

/* Collapsed sections: subtle chevron affordance */
.md-nav--primary .md-nav__item--nested > .md-nav__link::after {
  opacity: 0.55;
}