/* Header – premium, cinematic, neon accents */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background: var(--color-bg-overlay);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-gray-700);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-4);
  padding-bottom: var(--space-4);
}
.logo {
  font-family: var(--font-display);
  font-size: var(--font-size-2xl);
  font-weight: var(--font-weight-black);
  letter-spacing: -0.03em;
  text-decoration: none;
}
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  gap: 4px;
  background: transparent;
  border: none;
  cursor: pointer;
}
.nav-toggle-icon,
.nav-toggle-icon::before,
.nav-toggle-icon::after {
  content: '';
  display: block;
  height: 2px;
  width: 100%;
  background: var(--color-text-primary);
  border-radius: 2px;
  transition: transform var(--transition-base);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-icon {
  transform: rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-icon::before {
  transform: translateY(6px) rotate(-90deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-icon::after {
  opacity: 0;
}
.primary-nav .nav-list {
  display: flex;
  gap: var(--space-6);
  align-items: center;
}
.primary-nav a {
  font-family: var(--font-display);
  font-weight: var(--font-weight-medium);
  font-size: var(--font-size-sm);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-secondary);
  position: relative;
}
.primary-nav a:hover,
.primary-nav a:focus {
  color: var(--color-primary);
}
.primary-nav a::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -4px;
  width: 100%;
  height: 2px;
  background: var(--color-primary);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-base);
}
.primary-nav a:hover::after,
.primary-nav a:focus::after {
  transform: scaleX(1);
}
@media (max-width: 900px) {
  .nav-toggle {
    display: flex;
  }
  .primary-nav {
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background: var(--color-bg-overlay);
    backdrop-filter: blur(12px);
    border-top: 1px solid var(--color-gray-700);
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-base);
  }
  .primary-nav.is-open {
    max-height: 60vh;
    overflow-y: auto;
  }
  .primary-nav .nav-list {
    flex-direction: column;
    align-items: flex-start;
    padding: var(--space-6);
    gap: var(--space-4);
  }
  body.menu-open {
    overflow: hidden;
  }
}