.site-header {
  position: sticky;
  z-index: 100;
  top: 0;
  width: 100%;
  border-bottom: 1px solid var(--color-line);
  background: rgb(17 18 22 / 0.97);
  box-shadow: 0 8px 24px rgb(0 0 0 / 0.12);
}

.site-header__inner {
  display: flex;
  width: min(calc(100% - (var(--container-padding) * 2)), var(--container-max));
  min-height: 4.5rem;
  margin-inline: auto;
  align-items: center;
  gap: var(--space-3);
}

.site-header__brand {
  display: inline-flex;
  min-width: 0;
  flex: 1 1 auto;
  align-items: center;
  gap: 0.625rem;
  color: var(--color-ivory);
  text-decoration: none;
}

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

.site-header__mark {
  width: 2.5rem;
  height: 2.5rem;
  flex: 0 0 2.5rem;
  object-fit: contain;
}

.site-header__brand-name {
  overflow: hidden;
  font-family: var(--font-heading);
  font-size: 1.125rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.site-header__toggle {
  display: inline-flex;
  width: 2.75rem;
  min-width: 2.75rem;
  min-height: 2.75rem;
  flex: 0 0 2.75rem;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.3rem;
  padding: 0;
  border: 1px solid var(--color-line);
  background: transparent;
  color: var(--color-ivory);
}

.site-header__toggle:hover { border-color: var(--color-gold); background: transparent; color: var(--color-gold-bright); }

.site-header__toggle-line {
  display: block;
  width: 1.125rem;
  height: 1px;
  background: currentColor;
  transition: transform var(--transition-base), opacity var(--transition-base);
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-line:nth-child(1) { transform: translateY(0.4rem) 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:nth-child(3) { transform: translateY(-0.4rem) rotate(-45deg); }

.site-header__nav {
  position: absolute;
  z-index: 101;
  top: 100%;
  right: 0;
  left: 0;
  display: none;
  max-height: calc(100dvh - 4.5rem);
  overflow-y: auto;
  padding: var(--space-5) var(--container-padding) var(--space-6);
  border-bottom: 1px solid var(--color-line);
  background: var(--color-ink);
  box-shadow: var(--shadow-floating);
}

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

.site-header__nav-list {
  display: grid;
  gap: 0;
  margin: 0;
  padding: 0;
  list-style: none;
}

.site-header__nav-item,
.site-header__nav-item + .site-header__nav-item { margin: 0; padding: 0; }

.site-header__nav-link {
  display: flex;
  min-height: 2.75rem;
  align-items: center;
  padding-block: var(--space-2);
  border-bottom: 1px solid var(--color-line);
  color: var(--color-ivory);
  font-size: var(--text-meta);
  font-weight: 700;
  letter-spacing: 0.04em;
  text-decoration: none;
}

.site-header__nav-link:hover,
.site-header__nav-link:focus-visible { color: var(--color-gold-bright); }

.site-header__mobile-action { width: 100%; margin-top: var(--space-5); }
.site-header__action { display: none; white-space: nowrap; }

@media (min-width: 70rem) {
  .site-header__inner { min-height: 4.75rem; gap: var(--space-5); }
  .site-header__brand { flex: 0 1 auto; }
  .site-header__toggle { display: none; }
  .site-header__nav {
    position: static;
    display: block;
    max-height: none;
    flex: 1 1 auto;
    overflow: visible;
    padding: 0;
    border: 0;
    background: transparent;
    box-shadow: none;
  }
  .site-header__nav-list {
    display: flex;
    min-width: 0;
    justify-content: flex-end;
    align-items: center;
    gap: clamp(0.75rem, 1.4vw, 1.5rem);
  }
  .site-header__nav-link {
    min-height: 4.75rem;
    padding: 0;
    border: 0;
    white-space: nowrap;
  }
  .site-header__nav-link[aria-current="page"] { box-shadow: inset 0 -2px 0 var(--color-gold); }
  .site-header__nav-item--mobile,
  .site-header__mobile-action { display: none; }
  .site-header__action { display: inline-flex; flex: 0 0 auto; }
}

@media (max-width: 25rem) {
  .site-header__brand-name { font-size: 0.9375rem; }
}

@media (max-width: 22rem) {
  .site-header__brand-name { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); clip-path: inset(50%); white-space: nowrap; }
}