.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--color-surface-inverse);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 72px;
  gap: var(--space-4);
}

.brand {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  color: var(--color-text-inverse);
  text-decoration: none;
  flex-shrink: 0;
}

.brand-mark {
  height: 48px;
  width: auto;
}

.brand-text {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  color: var(--color-text-inverse);
}

.primary-nav {
  display: flex;
}

.nav-list {
  display: flex;
  gap: var(--space-4);
  align-items: center;
  margin: 0;
  padding: 0;
}

.nav-list li {
  margin: 0;
}

.nav-list a {
  color: var(--color-text-inverse);
  position: relative;
  padding: 4px 0;
}

.nav-list a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 0%;
  height: 2px;
  background: var(--color-accent-primary);
  transition: width var(--transition-fast);
}

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

.nav-toggle {
  display: none;
  gap: 4px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text-inverse);
}

@media (max-width: 900px) {
  .nav-toggle {
    display: flex;
    z-index: 1111;
  }

  .primary-nav {
    position: fixed;
    inset: 0 0 0 0;
    background: var(--color-surface-inverse);
    transform: translateX(-100%);
    transition: transform var(--transition-fast);
    padding: var(--space-5);
    overflow-y: auto;
  }

  .primary-nav.open {
    transform: translateX(0);
  }

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

  .brand-mark {
    height: 36px;
  }
}