/* ─────────────────────────────────────────
   nav.css — Fixed Top Navigation
   ───────────────────────────────────────── */

.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: var(--z-nav);
  display: flex;
  align-items: center;
  padding: 40px var(--gutter) 0;
  max-height: 120px;
  overflow: hidden;
  opacity: 1;
  pointer-events: none; /* re-enabled on children */
  transition: transform 320ms var(--ease-std), opacity 220ms ease;
}

/* Exclusion blend (cream + dark adaptive) applies to the links + menu icon
   only — never the brand logo, which must render full-color red. */
.site-nav__links,
.site-nav__hamburger {
  mix-blend-mode: exclusion;
}

/* Scroll-down hides the bar by sliding it up off the top (drag-away);
   scroll-up slides it back down. */
.site-nav.is-collapsed {
  /* !important so the collapse always wins over the home-intro entrance
     transform (html.has-opening:not(.opening-finished) .site-nav), which is
     more specific and would otherwise pin the bar in place on first visit. */
  transform: translateY(-100%) !important;
  opacity: 0;
  pointer-events: none;
}

/* ── Per-section blend overrides (set by IntersectionObserver in site.js) ── */

/* On red bg: disable the links/menu blend and force them white */
.site-nav.nav--on-red .site-nav__links,
.site-nav.nav--on-red .site-nav__hamburger {
  mix-blend-mode: normal;
}

.site-nav.nav--on-red .site-nav__links a,
.site-nav.nav--on-red .site-nav__logo img,
.site-nav.nav--on-red .site-nav__hamburger img {
  filter: brightness(0) invert(1);
  opacity: 0.9;
}

/* ── Logo ── */
.site-nav__logo {
  pointer-events: auto;
  flex-shrink: 0;
  line-height: 0;
}

.site-nav__logo img {
  height: 17px;
  width: auto;
  transition: opacity 0.25s var(--ease-std);
}

.site-nav__logo:hover img { opacity: 0.75; }

/* ── Links ── */
.site-nav__links {
  pointer-events: auto;
  display: flex;
  align-items: center;
  gap: clamp(24px, 3.3vw, 48px);
  margin-left: auto;
}

.site-nav__links a {
  font-family: var(--font-fustat);
  font-weight: 800;
  font-size: var(--fs-nav);
  line-height: 1;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: var(--nav-blue);
  white-space: nowrap;
  transition: opacity 0.2s var(--ease-std);
}

.site-nav__links a:hover { opacity: 0.65; }

/* ── Hamburger ── */
.site-nav__hamburger {
  pointer-events: auto;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 6px;
  margin-left: clamp(16px, 2vw, 32px);
  transition: opacity 0.2s var(--ease-std);
}

.site-nav__hamburger:hover { opacity: 0.7; }

.site-nav__hamburger img {
  display: block;
  width: 16px;
  height: auto;
  filter: none;
}

/* ── Mobile (< 1024px): simplify nav ── */
@media (max-width: 1023px) {
  .site-nav {
    padding-top: 24px;
  }

  .site-nav__links {
    display: none; /* hidden on mobile, use menu drawer instead */
  }

  .site-nav__hamburger {
    margin-left: auto;
  }
}