/* Sidebar navigation visual enhancements for clearer section separation */

/* Top-level section separators */
.md-nav--primary > .md-nav__list > .md-nav__item.md-nav__item--section {
  margin-top: 0.85rem;
  padding-top: 0.85rem;
  border-top: 1px solid var(--md-typeset-color);
}
.md-nav--primary > .md-nav__list > .md-nav__item.md-nav__item--section:first-of-type {
  border-top: none;
  margin-top: 0;
  padding-top: 0;
}

/* Section headings styling */
.md-nav--primary > .md-nav__list > .md-nav__item.md-nav__item--section > .md-nav__link {
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  font-size: 0.78rem;
  opacity: 0.85;
}

/* General link spacing */
.md-nav--primary .md-nav__link {
  position: relative;
  padding: 0.40rem 0.75rem;
  border-radius: 4px;
  transition: background-color 0.15s ease, color 0.15s ease;
}

/* Hover state */
.md-nav--primary .md-nav__link:hover {
  background-color: color-mix(in srgb, var(--md-primary-fg-color) 12%, transparent);
}

/* Active / current link highlight */
.md-nav--primary .md-nav__link[aria-current],
.md-nav--primary .md-nav__link.md-nav__link--active {
  background-color: color-mix(in srgb, var(--md-primary-fg-color) 20%, transparent);
  font-weight: 600;
  color: var(--md-primary-fg-color);
}

/* Active indicator bar */
.md-nav--primary .md-nav__link[aria-current]::before,
.md-nav--primary .md-nav__link.md-nav__link--active::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: var(--md-primary-fg-color);
  border-radius: 0 4px 4px 0;
}

/* Slightly tighter vertical rhythm for non-section items */
.md-nav--primary .md-nav__list .md-nav__item:not(.md-nav__item--section) {
  margin: 0.18rem 0;
}

/* Sub-list indentation subtle background grouping on hover */
.md-nav--primary .md-nav__list .md-nav__list .md-nav__link:hover {
  background-color: color-mix(in srgb, var(--md-primary-fg-color) 8%, transparent);
}

/* Improve focus outline visibility (keyboard navigation) */
.md-nav--primary .md-nav__link:focus {
  outline: 2px solid color-mix(in srgb, var(--md-primary-fg-color) 55%, transparent);
  outline-offset: 2px;
}

/* Optional: dim collapsed section content for contrast */
.md-nav--primary .md-nav__item--section[aria-expanded="false"] > .md-nav__list {
  opacity: 0.65;
}

@media (max-width: 959px) {
  /* Mobile sidebar tweaks */
  .md-nav--primary .md-nav__link {
    padding: 0.55rem 0.85rem;
  }
  .md-nav--primary > .md-nav__list > .md-nav__item.md-nav__item--section > .md-nav__link {
    font-size: 0.75rem;
  }
}

/* Collapsible section toggles */
.md-nav__item.collapsible > .md-nav__link {
  display: flex;
  align-items: center;
}

.md-nav__item.collapsible > .md-nav__link .nav-toggle {
  background: none;
  border: none;
  padding: 0 0.35rem 0 0;
  cursor: pointer;
  font-size: 0.75rem;
  line-height: 1;
  color: inherit;
  display: inline-flex;
  align-items: center;
  transition: transform 0.15s ease;
}

.md-nav__item.collapsible > .md-nav__link .nav-toggle[aria-expanded="true"] {
  font-weight: 600;
}

.md-nav__item.collapsible > .md-nav__link .nav-toggle:focus {
  outline: 2px solid color-mix(in srgb, var(--md-primary-fg-color) 55%, transparent);
  outline-offset: 2px;
  border-radius: 3px;
}

/* Provide slight indent to nested list after toggle button */
.md-nav__item.collapsible > .md-nav__list {
  margin-left: 0.25rem;
}

/* Smooth reveal */
.md-nav__item.collapsible > .md-nav__list {
  transition: height 0.2s ease;
}