/* Shared site chrome (header) used by every page: the landing page, the docs
   layout, and standalone pages. Relies on the design tokens (--ink, --gray,
   --line) declared in whichever base stylesheet the page also loads
   (home.css or style.css). Single source of truth so all headers match. */

:root {
  --header-h: 3.5rem;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.9rem 1.5rem;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(180%) blur(6px);
  border-bottom: 1px solid var(--line);
}

.site-header .brand {
  display: flex;
  align-items: baseline;
  gap: 0.9rem;
  min-width: 0;
}
.site-header .wordmark {
  font-size: 1.4rem;
  font-weight: 500;
  letter-spacing: 0.01em;
  text-decoration: none;
  color: var(--ink);
  white-space: nowrap;
}
.site-header .tagline {
  color: var(--gray);
  font-size: 0.95rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 1.4rem;
  font-size: 1rem;
  white-space: nowrap;
}
.site-nav a {
  color: var(--gray);
  text-decoration: none;
}
.site-nav a:hover { color: var(--ink); }
.site-nav a.active { color: var(--ink); }

/* On narrow screens drop the subtitle and stack the brand above the nav so
   the links never overflow. */
@media (max-width: 640px) {
  .site-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }
  .site-header .tagline { display: none; }
  .site-nav { gap: 1rem 1.2rem; }
}

/* A section placed directly under the header (e.g. standalone pages) should
   not draw its own top rule against the header's bottom rule. */
.site-header + .section { border-top: none; }