.site-header {
  position: relative;
  z-index: 100;
  background-color: var(--bg-elevated);
  border-bottom: 1px solid var(--border-subtle);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  min-height: 72px;
  padding-top: var(--space-3);
  padding-bottom: var(--space-3);
}

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

.site-header__brand:hover,
.site-header__brand:focus-visible {
  color: var(--accent-primary);
}

.site-header__logo {
  width: 36px;
  height: 36px;
  object-fit: contain;
  display: block;
}

.site-header__brand-text {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  line-height: 1.2;
  white-space: nowrap;
}

.site-header__nav {
  display: flex;
  align-items: center;
}

.site-header__nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-5);
  margin: 0;
  padding: 0;
  list-style: none;
}

.site-header__nav-list li {
  margin: 0;
  padding: 0;
}

.site-header__nav-list li + li {
  margin: 0;
}

.site-header__nav-link {
  display: inline-block;
  padding: var(--space-2) 0;
  font-family: var(--font-body);
  font-size: 0.9375rem;
  font-weight: 500;
  line-height: 1.4;
  color: var(--text-primary);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: color var(--transition-fast), border-color var(--transition-fast);
  white-space: nowrap;
}

.site-header__nav-link:hover,
.site-header__nav-link:focus-visible {
  color: var(--accent-primary);
  border-bottom-color: var(--accent-primary);
}

.site-header__nav-link[aria-current="page"] {
  color: var(--accent-primary);
  border-bottom-color: var(--accent-primary);
}

.nav-toggle {
  display: none;
}

@media (max-width: 1023px) {
  .site-header__inner {
    min-height: 64px;
  }

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

  .site-header__brand-text {
    font-size: 0.875rem;
  }

  .nav-toggle {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 5px;
    width: 44px;
    height: 44px;
    padding: 0;
    background: transparent;
    border: none;
    cursor: pointer;
    -webkit-tap-highlight-color: transparent;
    flex-shrink: 0;
  }

  .nav-toggle span {
    display: block;
    width: 22px;
    height: 2px;
    background-color: var(--text-primary);
    border-radius: 1px;
    transition: background-color var(--transition-fast), transform var(--transition-fast);
  }

  .nav-toggle:hover span,
  .nav-toggle:focus-visible span {
    background-color: var(--accent-primary);
  }

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

  .nav-toggle[aria-expanded="true"] span:nth-child(2) {
    opacity: 0;
  }

  .nav-toggle[aria-expanded="true"] span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .site-header__nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--bg-elevated);
    border-bottom: 1px solid var(--border-subtle);
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-medium);
    display: block;
  }

  .site-header__nav.is-open {
    max-height: calc(100vh - 64px);
    overflow-y: auto;
  }

  .site-header__nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: var(--space-4) var(--page-padding-mobile);
  }

  .site-header__nav-list li {
    width: 100%;
  }

  .site-header__nav-link {
    display: block;
    padding: var(--space-3) 0;
    font-size: 1.125rem;
    border-bottom: 1px solid var(--border-subtle);
  }

  .site-header__nav-link:hover,
  .site-header__nav-link:focus-visible {
    border-bottom-color: var(--accent-primary);
  }
}

@media (min-width: 640px) and (max-width: 1023px) {
  .site-header__nav-list {
    padding-inline: var(--page-padding-tablet);
  }
}