/* Header styles for PortalPL (builds on base.css) */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background: linear-gradient(180deg, var(--color-surface-elevated) 0%, var(--color-surface) 100%);
  border-bottom: 1px solid var(--color-neutral-700);
  box-shadow: var(--shadow-xs);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  min-height: 64px;
}

/* Brand */
.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  color: var(--color-text-primary);
}

.brand-mark {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-full);
  background: radial-gradient(closest-side, var(--color-accent) 0%, transparent 70%) center/100% 100% no-repeat,
              linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
  box-shadow: var(--shadow-glow);
}

.brand-text {
  font-family: var(--font-family-heading);
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  letter-spacing: -0.02em;
}

/* Navigation */
.primary-nav {
  display: block;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-6);
  list-style: none;
}

.nav-item a {
  color: var(--color-text-secondary);
  font-weight: var(--font-weight-medium);
}

.nav-item a:hover,
.nav-item a:focus-visible {
  color: var(--color-text-primary);
}

.nav-cta a.btn {
  box-shadow: var(--shadow-sm);
}

/* Mobile toggle */
.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--color-neutral-600);
  border-radius: var(--radius-base);
  padding: var(--space-2) var(--space-3);
  color: var(--color-text-primary);
}

.nav-toggle:hover {
  background-color: var(--color-surface);
}

.nav-toggle:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.nav-toggle-bar {
  width: 22px;
  height: 2px;
  background-color: var(--color-text-primary);
  display: block;
  margin: 2px 0;
  border-radius: 2px;
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

/* Transform bars when expanded */
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) { transform: translateY(6px) 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(-6px) rotate(-45deg); }

/* Responsive behavior */
@media (max-width: 767px) {
  .nav-toggle {
    display: inline-flex;
    flex-direction: column;
  }
  .nav-list { flex-direction: column; align-items: flex-start; gap: var(--space-4); }

  /* Progressive enhancement: hide menu on mobile only if JS enabled */
  html.js .primary-nav { position: absolute; top: 100%; left: 0; right: 0; display: none; }
  html.js .primary-nav.is-open { display: block; }

  .primary-nav {
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-neutral-700);
    box-shadow: var(--shadow-base);
    padding: var(--space-4) var(--space-4) var(--space-6);
  }

  .nav-cta a.btn { width: 100%; }
}