.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: var(--color-ink);
  border-bottom: var(--border-width) var(--border-style) var(--color-slate);
  height: var(--header-height-mobile);
  transition: height var(--transition-medium);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  height: 100%;
  max-width: var(--container-max-width);
  margin-inline: auto;
  padding-inline: var(--container-padding-mobile);
}

.site-header__brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  text-decoration: none;
  color: var(--color-bone);
  flex-shrink: 0;
  min-width: 0;
}

.site-header__logo {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
}

.site-header__brand-text {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: var(--font-weight-subhead);
  letter-spacing: 0.02em;
  color: var(--color-bone);
  white-space: nowrap;
}

.site-header__toggle {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: var(--touch-target-min);
  height: var(--touch-target-min);
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 0;
  flex-shrink: 0;
}

.site-header__toggle-line {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--color-bone);
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-line:nth-child(1) {
  transform: translateY(7px) 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(-7px) rotate(-45deg);
}

.site-header__toggle:focus-visible {
  outline: var(--focus-ring-width) var(--border-style) var(--focus-ring-color);
  outline-offset: var(--focus-ring-offset);
}

.site-header__nav {
  position: fixed;
  top: 0;
  right: 0;
  bottom: 0;
  width: min(320px, 85vw);
  max-width: 100%;
  background-color: var(--color-ink);
  border-left: var(--border-width) var(--border-style) var(--color-slate);
  transform: translateX(100%);
  visibility: hidden;
  transition: transform var(--transition-medium), visibility var(--transition-medium);
  overflow-y: auto;
  z-index: 1001;
  padding: var(--space-2xl) var(--space-lg);
}

.site-header__close {
  position: absolute;
  top: var(--space-md);
  right: var(--space-md);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: var(--touch-target-min);
  height: var(--touch-target-min);
  padding: 0;
  background: transparent;
  border: none;
  cursor: pointer;
}

.site-header__close-line {
  position: absolute;
  width: 22px;
  height: 2px;
  background-color: var(--color-bone);
}

.site-header__close-line:first-child {
  transform: rotate(45deg);
}

.site-header__close-line:last-child {
  transform: rotate(-45deg);
}

.site-header__close:focus-visible {
  outline: var(--focus-ring-width) var(--border-style) var(--focus-ring-color);
  outline-offset: var(--focus-ring-offset);
}

.site-header__nav.is-open {
  transform: translateX(0);
  visibility: visible;
}

.site-header__nav-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  margin: 0;
  padding: 0;
  list-style: none;
}

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

.site-header__nav-link {
  display: block;
  font-size: 1.5rem;
  line-height: 1.2;
  font-weight: var(--font-weight-subhead);
  color: var(--color-bone);
  text-decoration: none;
  padding: var(--space-sm) 0;
  transition: color var(--transition-fast);
}

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

.site-header__nav-link:focus-visible {
  outline: var(--focus-ring-width) var(--border-style) var(--focus-ring-color);
  outline-offset: var(--focus-ring-offset);
}

@media (min-width: 768px) {
  .site-header {
    height: var(--header-height-desktop);
  }

  .site-header__inner {
    padding-inline: var(--container-padding-tablet);
  }

  .site-header__logo {
    width: 36px;
    height: 36px;
  }

  .site-header__brand-text {
    font-size: 1.125rem;
  }

  .site-header__toggle {
    display: none;
  }

  .site-header__nav {
    position: static;
    transform: none;
    visibility: visible;
    width: auto;
    max-width: none;
    background: transparent;
    border-left: none;
    overflow-y: visible;
    padding: 0;
    z-index: auto;
  }

  .site-header__close {
    display: none;
  }

  .site-header__nav-list {
    flex-direction: row;
    align-items: center;
    gap: var(--space-lg);
  }

  .site-header__nav-link {
    font-size: 0.875rem;
    line-height: 1.2;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    padding: var(--space-xs) 0;
  }
}

@media (min-width: 1200px) {
  .site-header__inner {
    padding-inline: var(--container-padding-desktop);
  }
}

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