.site-header {
  position: sticky;
  z-index: 100;
  top: 0;
  border-bottom: 1px solid rgba(14, 46, 78, 0.1);
  background: rgba(249, 249, 249, 0.94);
  backdrop-filter: blur(16px);
}

.nav-shell {
  display: grid;
  min-height: 5.5rem;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 2rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  text-decoration: none;
}

.brand img {
  width: 2.8rem;
  height: 2.8rem;
  object-fit: contain;
}

.brand-mark { position: relative; width: 2.8rem; height: 2.8rem; flex: 0 0 auto; display: grid; place-items: center; border: 1px solid rgba(14, 46, 78, 0.24); border-radius: 50%; transform: rotate(12deg); }
.brand-mark::before,
.brand-mark::after,
.brand-mark i::before,
.brand-mark i::after { position: absolute; width: 1.85rem; height: 1px; background: var(--navy-700); content: ""; }
.brand-mark::after { transform: rotate(90deg); }
.brand-mark i::before { transform: rotate(45deg); }
.brand-mark i::after { transform: rotate(-45deg); }
.brand-mark i { width: 0.48rem; aspect-ratio: 1; border-radius: 50%; background: var(--warm-500); box-shadow: 0 0 0 0.25rem rgba(228, 164, 92, 0.14); }

.brand__name {
  display: block;
  color: var(--navy-900);
  font-family: var(--font-display);
  font-size: 1.32rem;
  font-weight: 700;
  letter-spacing: 0.11em;
  line-height: 1;
  text-transform: uppercase;
}

.brand__school {
  display: block;
  margin-top: 0.35rem;
  color: var(--navy-500);
  font-size: 0.66rem;
  font-weight: 800;
  letter-spacing: 0.17em;
  line-height: 1;
  text-transform: uppercase;
}

.nav-links {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: clamp(1rem, 2.4vw, 2.25rem);
}

.nav-links > a {
  position: relative;
  padding: 0.65rem 0;
  border: 0;
  background: transparent;
  color: var(--navy-900);
  font-size: 0.88rem;
  font-weight: 750;
  text-decoration: none;
  cursor: pointer;
}

.nav-links > a::after {
  position: absolute;
  right: 0;
  bottom: 0.25rem;
  left: 0;
  height: 1px;
  background: currentColor;
  content: "";
  transform: scaleX(0);
  transform-origin: right;
  transition: transform var(--transition);
}

.nav-links > a:hover::after,
.nav-links > a[aria-current="page"]::after {
  transform: scaleX(1);
  transform-origin: left;
}

.nav-dropdown { position: relative; }
.nav-dropdown__trigger { position: relative; display: inline-flex; align-items: center; gap: 0.35rem; padding: 0.65rem 0; color: var(--navy-900); font-size: 0.88rem; font-weight: 750; text-decoration: none; }
.nav-dropdown__trigger::before { content: ""; position: absolute; right: 0; bottom: 0.25rem; left: 0; height: 1px; background: currentColor; transform: scaleX(0); transform-origin: right; transition: transform var(--transition); }
.nav-dropdown__trigger::after { content: "⌄"; color: var(--warm-500); font-size: 0.8rem; }
.nav-dropdown:hover .nav-dropdown__trigger::before, .nav-dropdown:focus-within .nav-dropdown__trigger::before, .nav-dropdown__trigger[aria-current="page"]::before { transform: scaleX(1); transform-origin: left; }
.nav-dropdown__menu { position: absolute; min-width: 12rem; top: calc(100% + 0.2rem); left: 50%; display: grid; padding: 0.55rem; border: 1px solid var(--line-dark); background: var(--paper); box-shadow: var(--shadow-sm); opacity: 0; pointer-events: none; transform: translate(-50%, 0.4rem); transition: opacity var(--transition), transform var(--transition); }
.nav-dropdown:hover .nav-dropdown__menu, .nav-dropdown:focus-within .nav-dropdown__menu { opacity: 1; pointer-events: auto; transform: translate(-50%, 0); }
.nav-dropdown__menu a { padding: 0.65rem 0.75rem; color: var(--navy-900); font-size: 0.82rem; font-weight: 700; text-decoration: none; }
.nav-dropdown__menu a:hover, .nav-dropdown__menu a:focus-visible { background: var(--paper-warm); }

.nav-login {
  padding: 0.75rem 1rem !important;
  border: 1px solid var(--navy-800) !important;
  border-radius: var(--radius-sm);
}

.nav-login:hover {
  background: var(--navy-800) !important;
  color: var(--white) !important;
}

.nav-login::after {
  display: none;
}

.menu-toggle {
  display: none;
  width: 2.8rem;
  height: 2.8rem;
  border: 1px solid var(--line-dark);
  border-radius: 50%;
  background: transparent;
  color: var(--navy-900);
  cursor: pointer;
}

.menu-toggle span,
.menu-toggle::before,
.menu-toggle::after {
  display: block;
  width: 1.15rem;
  height: 1px;
  margin: 0.28rem auto;
  background: currentColor;
  content: "";
}