.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: var(--color-background);
  border-bottom: var(--border-width) solid var(--color-border);
}

.site-header__inner {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: var(--space-4);
  max-width: var(--container-max);
  margin-inline: auto;
  padding: var(--space-3) var(--container-padding);
  min-height: 72px;
}

.site-header__zone {
  display: flex;
  align-items: center;
  min-width: 0;
}

.site-header__zone--left {
  justify-content: flex-start;
}

.site-header__zone--center {
  justify-content: center;
}

.site-header__zone--right {
  justify-content: flex-end;
}

.site-header__brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-text-primary);
  min-width: 0;
  flex-shrink: 0;
}

.site-header__logo {
  width: 48px;
  height: 48px;
  object-fit: contain;
  display: block;
  flex-shrink: 0;
}

.site-header__brand-text {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  line-height: 1;
  text-transform: uppercase;
  white-space: nowrap;
  letter-spacing: 0.02em;
}

.site-header__nav {
  display: block;
}

.site-header__nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  list-style: none;
  margin: 0;
  padding: 0;
}

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

.site-header__nav-link {
  display: inline-block;
  padding: var(--space-2) var(--space-3);
  font-family: var(--font-heading);
  font-size: 0.875rem;
  line-height: 1;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--color-text-primary);
  white-space: nowrap;
  transition: color var(--transition-duration) var(--transition-ease),
    background-color var(--transition-duration) var(--transition-ease);
}

.site-header__nav-link:hover {
  color: var(--color-text-on-accent);
  background-color: var(--color-accent);
}

.site-header__nav-link:focus-visible {
  outline: var(--border-width) solid var(--color-accent);
  outline-offset: 2px;
}

.site-header__toggle {
  display: none;
  grid-column: 3;
  justify-self: end;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  padding: 0;
  background: transparent;
  border: var(--border-width) solid var(--color-border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: background-color var(--transition-duration) var(--transition-ease),
    border-color var(--transition-duration) var(--transition-ease);
}

.site-header__toggle:hover {
  background-color: var(--color-surface);
}

.site-header__toggle:focus-visible {
  outline: var(--border-width) solid var(--color-accent);
  outline-offset: 2px;
}

.site-header__toggle-icon,
.site-header__toggle-icon::before,
.site-header__toggle-icon::after {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-text-primary);
  transition: transform var(--transition-duration) var(--transition-ease),
    opacity var(--transition-duration) var(--transition-ease);
}

.site-header__toggle-icon {
  position: relative;
}

.site-header__toggle-icon::before,
.site-header__toggle-icon::after {
  content: "";
  position: absolute;
  left: 0;
}

.site-header__toggle-icon::before {
  top: -8px;
}

.site-header__toggle-icon::after {
  top: 8px;
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-icon {
  background-color: transparent;
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-icon::before {
  transform: translateY(8px) rotate(45deg);
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-icon::after {
  transform: translateY(-8px) rotate(-45deg);
}

.site-header__mobile-nav {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  z-index: 999;
  background-color: var(--color-background);
  border-bottom: var(--border-width) solid var(--color-border);
  max-height: calc(100vh - 72px);
  overflow-y: auto;
  padding: var(--space-4) var(--container-padding);
}

.site-header__mobile-nav[hidden] {
  display: none;
}

.site-header__mobile-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

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

.site-header__mobile-link {
  display: block;
  padding: var(--space-3);
  font-family: var(--font-heading);
  font-size: 1rem;
  line-height: 1.2;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--color-text-primary);
  border: var(--border-width) solid transparent;
  transition: color var(--transition-duration) var(--transition-ease),
    background-color var(--transition-duration) var(--transition-ease),
    border-color var(--transition-duration) var(--transition-ease);
}

.site-header__mobile-link:hover {
  color: var(--color-text-on-accent);
  background-color: var(--color-accent);
  border-color: var(--color-border);
}

.site-header__mobile-link:focus-visible {
  outline: var(--border-width) solid var(--color-accent);
  outline-offset: 2px;
}

@media (max-width: 1024px) {
  .site-header__inner {
    grid-template-columns: auto 1fr auto;
  }

  .site-header__zone--left,
  .site-header__zone--right {
    display: none;
  }

  .site-header__zone--center {
    justify-content: flex-start;
  }

  .site-header__toggle {
    display: flex;
  }
}

@media (max-width: 768px) {
  .site-header__inner {
    min-height: 64px;
    padding: var(--space-2) var(--container-padding);
  }

  .site-header__logo {
    width: 40px;
    height: 40px;
  }

  .site-header__brand-text {
    font-size: 1rem;
  }

  .site-header__mobile-nav {
    max-height: calc(100vh - 64px);
  }
}