/* Header layout */
.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background-color: rgba(245, 247, 251, 0.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
}

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

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

.header-logo {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
}

.header-logo-mark {
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 0.9rem;
  background: radial-gradient(circle at 30% 20%, #e0f5fd, var(--color-primary));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1rem;
  color: #ffffff;
  box-shadow: var(--shadow-md);
}

.header-logo-text {
  display: flex;
  flex-direction: column;
}

.header-logo-name {
  font-weight: 600;
  font-size: var(--font-size-lg);
  color: var(--gray-900);
}

.header-logo-tagline {
  font-size: var(--font-size-xs);
  color: var(--color-muted);
}

/* Navigation */
.header-nav {
  margin-left: auto;
}

.header-nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  list-style: none;
}

.header-nav-link {
  position: relative;
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--gray-700);
  padding: 0.25rem 0;
}

.header-nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -0.1rem;
  width: 0;
  height: 2px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-success));
  transition: width var(--transition-base);
}

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

.header-nav-cta {
  margin-left: var(--space-2);
}

.header-cta {
  font-size: var(--font-size-sm);
  padding-inline: 1.25rem;
  padding-block: 0.55rem;
  white-space: nowrap;
}

/* Mobile toggle */
.header-toggle {
  display: none;
  align-items: center;
  gap: var(--space-2);
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-pill);
  border: 1px solid var(--color-border);
  background-color: #ffffff;
  cursor: pointer;
}

.header-toggle-box {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
}

.header-toggle-line {
  width: 20px;
  height: 2px;
  background-color: var(--gray-800);
  border-radius: 999px;
  transition: transform var(--transition-base), opacity var(--transition-base);
}

.header-toggle-text {
  font-size: var(--font-size-xs);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--gray-700);
}

/* Toggle animation */
.header-toggle[aria-expanded="true"] .header-toggle-line:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

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

.header-toggle[aria-expanded="true"] .header-toggle-line:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

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

  .header-logo-name {
    font-size: 1rem;
  }

  .header-logo-tagline {
    display: none;
  }

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

  .header-nav {
    position: absolute;
    inset-inline: 0;
    top: 100%;
    background-color: #ffffff;
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-md);
    transform-origin: top;
    transform: scaleY(0.96);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transition: opacity var(--transition-base), transform var(--transition-base), visibility var(--transition-base);
  }

  .header-nav-list {
    flex-direction: column;
    align-items: flex-start;
    padding: var(--space-3) var(--space-4) var(--space-4);
    gap: var(--space-2);
  }

  .header-nav-cta {
    width: 100%;
    margin-left: 0;
    margin-top: var(--space-2);
  }

  .header-cta {
    width: 100%;
    justify-content: center;
  }

  .header-nav.is-open {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: scaleY(1);
  }
}

@media (min-width: 769px) {
  .header-nav {
    position: static;
  }
}

/* Focus styles refinement */
.header-nav-link:focus-visible,
.header-logo:focus-visible,
.header-toggle:focus-visible {
  box-shadow: 0 0 0 2px var(--color-primary-soft), 0 0 0 4px rgba(14, 165, 233, 0.4);
  border-radius: var(--radius-pill);
}

.header-logo:focus-visible {
  outline: none;
}