.site-header {
  background: var(--surface-page);
  border-block-end: var(--border-default);
  color: var(--color-ink);
  position: relative;
  z-index: 100;
}

.site-header__inner {
  align-items: center;
  display: flex;
  gap: var(--space-4);
  justify-content: space-between;
  min-block-size: 5rem;
  position: relative;
}

.site-header__brand {
  align-items: center;
  color: var(--color-ink);
  display: inline-flex;
  flex: 0 1 auto;
  gap: var(--space-3);
  min-inline-size: 0;
  text-decoration: none;
}

.site-header__brand:hover { color: var(--color-ink); }

.site-header__mark {
  block-size: 2.125rem;
  flex: 0 0 2.125rem;
  inline-size: 2.125rem;
  object-fit: contain;
}

.site-header__brand-copy {
  display: grid;
  gap: 0.1rem;
  min-inline-size: 0;
}

.site-header__name {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: -0.025em;
  line-height: 1.05;
  white-space: nowrap;
}

.site-header__descriptor {
  color: var(--color-text-muted);
  font-size: 0.625rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  line-height: 1.2;
  text-transform: uppercase;
  white-space: nowrap;
}

.site-header__toggle {
  align-items: center;
  background: transparent;
  border: 1px solid var(--color-ink);
  border-radius: var(--radius-card);
  display: inline-flex;
  flex: 0 0 2.75rem;
  flex-direction: column;
  gap: 0.25rem;
  inline-size: 2.75rem;
  justify-content: center;
  min-block-size: 2.75rem;
  padding: 0;
}

.site-header__toggle-line {
  background: currentColor;
  block-size: 2px;
  inline-size: 1.125rem;
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-line:first-child { transform: translateY(0.375rem) rotate(45deg); }
.site-header__toggle[aria-expanded="true"] .site-header__toggle-line:nth-child(2) { opacity: 0; }
.site-header__toggle[aria-expanded="true"] .site-header__toggle-line:last-child { transform: translateY(-0.375rem) rotate(-45deg); }

.site-header__nav {
  background: var(--surface-page);
  border-block-start: var(--border-default);
  display: none;
  inset-inline: 0;
  max-block-size: calc(100vh - 5rem);
  overflow-y: auto;
  position: absolute;
  top: 100%;
}

.site-header__nav.is-open { display: block; }

.site-header__nav-inner {
  display: grid;
  gap: var(--space-5);
  padding: var(--space-5) var(--gutter) var(--space-6);
}

.site-header__links,
.site-header__actions {
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-header__links {
  display: grid;
  gap: var(--space-2);
}

.site-header__links li,
.site-header__links li + li { margin: 0; }

.site-header__links a {
  align-items: center;
  color: var(--color-ink);
  display: flex;
  font-size: var(--text-label);
  font-weight: 700;
  min-block-size: 2.75rem;
  text-decoration: none;
}

.site-header__links a:hover,
.site-header__links a[aria-current="page"] { color: var(--color-cobalt); }

.site-header__actions {
  display: grid;
  gap: var(--space-3);
}

.site-header__actions .button { inline-size: 100%; }

@media (min-width: 56.25rem) {
  .site-header__inner { min-block-size: 5.5rem; }
  .site-header__mark { block-size: 2.625rem; flex-basis: 2.625rem; inline-size: 2.625rem; }
  .site-header__name { font-size: 1.125rem; }
  .site-header__toggle { display: none; }
  .site-header__nav {
    background: transparent;
    border: 0;
    display: block;
    inset: auto;
    max-block-size: none;
    overflow: visible;
    position: static;
  }
  .site-header__nav-inner {
    align-items: center;
    display: flex;
    gap: var(--space-4);
    justify-content: flex-end;
    padding: 0;
  }
  .site-header__links {
    align-items: center;
    display: flex;
    gap: 0.2rem;
  }
  .site-header__links a {
    font-size: 0.75rem;
    min-block-size: 2.75rem;
    padding-inline: 0.35rem;
    white-space: nowrap;
  }
  .site-header__mobile-only { display: none; }
  .site-header__actions {
    display: flex;
    gap: var(--space-2);
  }
  .site-header__actions .button {
    font-size: 0.75rem;
    inline-size: auto;
    padding-inline: 0.7rem;
    white-space: nowrap;
  }
}

@media (min-width: 75rem) {
  .site-header__nav-inner { gap: var(--space-5); }
  .site-header__links { gap: var(--space-2); }
  .site-header__links a { font-size: var(--text-label); padding-inline: 0.45rem; }
  .site-header__actions .button { font-size: var(--text-label); padding-inline: 1rem; }
}

@media (max-width: 25rem) {
  .site-header__inner { gap: var(--space-2); }
  .site-header__descriptor { display: none; }
  .site-header__name { font-size: 0.875rem; }
}

@media (prefers-reduced-motion: reduce) {
  .site-header__toggle-line { transition: none; }
}