/* Header styles scoped to .site-header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border-subtle);
  backdrop-filter: blur(10px);
}

.skip-link {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  top: -3rem;
  padding: 0.5rem 1rem;
  background: var(--color-accent-navy);
  color: #fff;
  border-radius: var(--radius-full);
  font-size: var(--font-size-sm);
  z-index: 60;
}

.skip-link:focus {
  top: 0.75rem;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-3);
  padding-bottom: var(--space-3);
}

.header-brand {
  display: flex;
  align-items: center;
}

.brand-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  color: inherit;
}

.brand-mark {
  display: grid;
  grid-template-columns: repeat(2, 10px);
  grid-auto-rows: 10px;
  gap: 2px;
  padding: 6px;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border-subtle);
  background-color: var(--color-surface);
  box-shadow: var(--shadow-xs);
}

.brand-cell {
  width: 10px;
  height: 10px;
  border-radius: 2px;
  background-color: var(--color-neutral-100);
}

.brand-cell--accent {
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent-green));
}

.brand-cell--accent-soft {
  background-color: var(--color-primary-soft);
}

.brand-text {
  display: flex;
  flex-direction: column;
}

.brand-title {
  font-size: var(--font-size-lg);
  font-weight: 600;
  letter-spacing: -0.03em;
  color: var(--color-accent-navy);
}

.brand-subtitle {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
}

.site-nav {
  display: flex;
  align-items: center;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.nav-link {
  position: relative;
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  padding: 0.25rem 0;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -0.25rem;
  width: 0;
  height: 2px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-accent-green));
  transition: width var(--transition-base);
}

.nav-link:hover,
.nav-link:focus-visible {
  color: var(--color-accent-navy);
}

.nav-link:hover::after,
.nav-link:focus-visible::after {
  width: 100%;
}

.nav-item--cta .nav-link--cta {
  padding: 0.45rem 0.9rem;
  border-radius: var(--radius-full);
  border: 1px solid var(--color-border-subtle);
  background-color: var(--color-surface);
  color: var(--color-accent-navy);
  font-weight: 500;
}

.nav-item--cta .nav-link--cta:hover,
.nav-item--cta .nav-link--cta:focus-visible {
  background-color: var(--color-primary-soft);
  border-color: var(--color-primary);
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: var(--space-2);
  padding: 0.3rem 0.7rem;
  border-radius: var(--radius-full);
  border: 1px solid var(--color-border-subtle);
  background-color: var(--color-surface);
  cursor: pointer;
}

.nav-toggle-box {
  position: relative;
  width: 18px;
  height: 14px;
}

.nav-toggle-bar {
  position: absolute;
  left: 0;
  right: 0;
  height: 2px;
  border-radius: 999px;
  background-color: var(--color-accent-navy);
  transition: transform var(--transition-base), opacity var(--transition-base), top var(--transition-base), bottom var(--transition-base);
}

.nav-toggle-bar:first-child {
  top: 2px;
}

.nav-toggle-bar:last-child {
  bottom: 2px;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:first-child {
  top: 6px;
  transform: rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:last-child {
  bottom: 6px;
  transform: rotate(-45deg);
}

.nav-toggle-text {
  font-size: var(--font-size-xs);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-muted);
}

/* Mobile layout */
@media (max-width: 768px) {
  .header-inner {
    padding-top: var(--space-2);
    padding-bottom: var(--space-2);
  }

  .nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    position: absolute;
    inset-inline: 0;
    top: 100%;
    background-color: var(--color-bg);
    border-bottom: 1px solid var(--color-border-subtle);
    box-shadow: var(--shadow-md);
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: var(--space-2) var(--space-4) var(--space-4);
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
    transition:
      max-height var(--transition-slow),
      opacity var(--transition-base),
      visibility var(--transition-base);
  }

  .nav-list.is-open {
    max-height: 400px;
    opacity: 1;
    visibility: visible;
  }

  .nav-item {
    padding-block: 0.25rem;
  }

  .nav-link {
    display: inline-block;
    width: 100%;
    padding-block: 0.5rem;
  }

  .nav-item--cta .nav-link--cta {
    width: auto;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .nav-list {
    transition: none;
  }
  .nav-toggle-bar {
    transition: none;
  }
}