.site-header {
  position: relative;
  z-index: 1000;
  background-color: var(--bg-base);
  border-bottom: 1px solid var(--border-subtle);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  min-height: 64px;
  padding-block: var(--space-2);
}

.site-header__brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  text-decoration: none;
  color: var(--text-primary);
  min-width: 0;
  flex-shrink: 0;
}

.site-header__brand:hover {
  color: var(--text-primary);
  text-decoration: none;
}

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

.site-header__brand-text {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: var(--heading-letter-spacing);
  white-space: nowrap;
}

.site-header__toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  padding: 0;
  background: none;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  cursor: pointer;
  transition: border-color 0.2s ease, background-color 0.2s ease;
  flex-shrink: 0;
}

.site-header__toggle:hover {
  border-color: var(--accent-gold);
  background-color: var(--bg-elevated);
}

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

.site-header__toggle-icon,
.site-header__toggle-icon::before,
.site-header__toggle-icon::after {
  display: block;
  width: 20px;
  height: 2px;
  background-color: currentColor;
  border-radius: 1px;
  transition: transform 0.3s ease, opacity 0.3s ease;
  position: relative;
}

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

.site-header__toggle-icon::before {
  top: -6px;
}

.site-header__toggle-icon::after {
  top: 6px;
}

.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(6px) rotate(45deg);
}

.site-header__toggle[aria-expanded="true"] .site-header__toggle-icon::after {
  transform: translateY(-6px) rotate(-45deg);
}

.site-header__nav {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  background-color: var(--bg-base);
  border-bottom: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-modal);
  max-height: calc(100vh - 100%);
  overflow-y: auto;
  z-index: 999;
}

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

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

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

.site-header__nav-link {
  display: block;
  padding: var(--space-2) var(--space-4);
  color: var(--text-primary);
  font-size: var(--body-size);
  font-weight: 500;
  text-decoration: none;
  transition: color 0.2s ease, background-color 0.2s ease;
}

.site-header__nav-link:hover {
  color: var(--accent-gold);
  background-color: var(--bg-surface);
  text-decoration: none;
}

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

@media (min-width: 768px) {
  .site-header__inner {
    min-height: 72px;
  }

  .site-header__logo {
    width: 56px;
    height: 56px;
  }

  .site-header__brand-text {
    font-size: 1.5rem;
  }

  .site-header__toggle {
    display: none;
  }

  .site-header__nav {
    display: block;
    position: static;
    background: none;
    border: none;
    box-shadow: none;
    max-height: none;
    overflow: visible;
  }

  .site-header__nav-list {
    flex-direction: row;
    align-items: center;
    gap: var(--space-4);
    padding: 0;
  }

  .site-header__nav-link {
    padding: var(--space-1) 0;
    position: relative;
  }

  .site-header__nav-link::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: 0;
    width: 100%;
    height: 2px;
    background-color: var(--accent-gold);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.2s ease;
  }

  .site-header__nav-link:hover::after,
  .site-header__nav-link:focus-visible::after {
    transform: scaleX(1);
  }

  .site-header__nav-link:hover {
    background: none;
  }
}

@media (min-width: 1024px) {
  .site-header__logo {
    width: 64px;
    height: 64px;
  }

  .site-header__brand-text {
    font-size: 1.75rem;
  }

  .site-header__nav-list {
    gap: var(--space-5);
  }
}