.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  height: var(--gc-header-h);
  background: rgba(244, 247, 251, 0.86);
  border-bottom: 1px solid transparent;
  backdrop-filter: blur(14px);
  transition: background var(--gc-transition), border-color var(--gc-transition), box-shadow var(--gc-transition);
}

.site-header.is-scrolled {
  background: rgba(255, 255, 255, 0.94);
  border-bottom-color: var(--gc-border);
  box-shadow: 0 8px 24px rgba(22, 31, 76, 0.08);
}

.header-inner {
  width: min(100% - 2rem, var(--gc-container));
  height: 100%;
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--gc-space-4);
}

.site-branding {
  display: flex;
  align-items: center;
  min-width: 0;
}

.primary-navigation {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 0.15rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.nav-menu a {
  display: block;
  padding: 0.55rem 0.8rem;
  color: var(--gc-ink-soft);
  font-size: 0.95rem;
  font-weight: 550;
  text-decoration: none;
  border-radius: var(--gc-radius);
  transition: color var(--gc-transition), background var(--gc-transition);
}

.nav-menu a:hover,
.nav-menu a:focus-visible,
.nav-menu .current-menu-item > a {
  color: var(--gc-blue);
  background: rgba(21, 134, 211, 0.1);
}

.nav-toggle {
  display: none;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0;
  border: 1px solid var(--gc-border);
  border-radius: var(--gc-radius);
  background: var(--gc-surface);
  cursor: pointer;
}

.nav-toggle-bar {
  display: block;
  width: 1.15rem;
  height: 2px;
  margin: 0.28rem auto;
  background: var(--gc-ink);
  transition: transform var(--gc-transition), opacity var(--gc-transition);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) {
  transform: translateY(6.5px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) {
  transform: translateY(-6.5px) rotate(-45deg);
}

body.nav-open {
  overflow: hidden;
}