/* Mobile presentation: show mobile nav, hide desktop nav */
.nav-desktop { display: none; }
.nav-mobile { display: block; }

/* Keep header light in mobile */
header {
  background: var(--c-bg);
  color: var(--c-fg);
  border-bottom: 1px solid var(--c-border);
  position: relative;
}
header a { color: inherit; }
header a:hover { color: inherit; }

.nav-mobile details.menu > summary {
  cursor: pointer;
  user-select: none;
  display: inline-block;
  padding: 0.5rem 0.75rem;
  border-radius: 0.5rem;
  background: var(--c-nav-bg);
  color: var(--c-nav-fg);
  border: 1px solid var(--c-nav-border);
}

/* Ensure overlay is NEVER visible unless details is open */
.nav-mobile details.menu .menu-overlay {
  display: none;
}
.nav-mobile details.menu[open] .menu-overlay {
  display: block;

  position: absolute;
  left: 0;
  right: 0;
  top: 100%;
  margin-top: 0.5rem;

  z-index: 999;
  background: var(--c-bg);
  color: var(--c-fg);
  border: 1px solid var(--c-border);
  border-radius: 10px;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
  padding: 0.5rem;
}

.nav-mobile .menu-overlay ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: block;
}

.nav-mobile .menu-overlay li + li {
  border-top: 1px solid var(--c-border);
}

.nav-mobile .menu-overlay a {
  display: block;
  padding: 0.9rem 0.75rem;
  font-size: 1.1rem;
  text-decoration: none;
  color: var(--c-link);
}
.nav-mobile .menu-overlay a:hover {
  background: rgba(0, 0, 0, 0.04);
  color: var(--c-link-hover);
}