/* Shared first-party page header. Keep page-specific content and actions intact. */
:root {
  --vn-header-bg: var(--vn-surface, var(--seed-header-bg, var(--surface, #ffffff)));
  --vn-header-text: var(--vn-text-strong, var(--seed-text-bright, var(--text-strong, #111111)));
  --vn-header-muted: var(--vn-text-muted, var(--seed-muted, var(--text-muted, #666666)));
  --vn-header-border: var(--vn-border, var(--seed-border, var(--border, rgba(0, 0, 0, 0.12))));
  --vn-header-border-strong: var(--vn-border-strong, var(--seed-border-strong, var(--border-strong, rgba(0, 0, 0, 0.2))));
  --vn-header-hover: var(--vn-surface-hover, var(--seed-surface-2, var(--surface-2, rgba(0, 0, 0, 0.055))));
  --vn-header-focus: var(--vn-primary, var(--seed-primary, var(--primary, #2563eb)));
  --vn-header-action: var(--vn-text, var(--seed-text, var(--text, #222222)));
}

html[data-theme='dark'],
html.dark,
body.dark,
[data-theme='dark'] {
  --vn-header-text: var(--vn-text-strong, var(--seed-text-bright, var(--text-strong, #ffffff)));
  --vn-header-muted: var(--vn-text-muted, var(--seed-muted, var(--text-muted, #b6b6b6)));
  --vn-header-action: var(--vn-text, var(--seed-text, var(--text, #f2f2f2)));
}

.vn-topbar {
  box-sizing: border-box;
  display: flex;
  align-items: center;
  gap: 16px;
  width: 100%;
  min-height: 58px;
  padding: 8px clamp(14px, 3vw, 24px);
  color: var(--vn-header-action);
  background: var(--vn-header-bg);
  border-bottom: 1px solid var(--vn-header-border);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  position: relative;
  z-index: 20;
}

.vn-topbar-leading {
  display: flex;
  align-items: center;
  min-width: 0;
  min-height: 42px;
  flex: 1 1 auto;
}

.vn-topbar-brand {
  display: inline-flex;
  align-items: center;
  min-width: 0;
  min-height: 42px;
  color: var(--vn-header-text);
  text-decoration: none;
  white-space: nowrap;
}

.vn-topbar-brand:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--vn-header-focus) 42%, transparent);
  outline-offset: 4px;
  border-radius: 4px;
}

.vn-topbar-name {
  color: var(--vn-header-text);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.01em;
  line-height: 1.35;
}

.vn-topbar-divider {
  width: 1px;
  height: 18px;
  margin: 0 12px;
  background: var(--vn-header-border-strong);
  flex: 0 0 auto;
}

.vn-topbar-sub {
  min-width: 0;
  overflow: hidden;
  color: var(--vn-header-muted);
  font-size: 14px;
  font-weight: 400;
  line-height: 1.4;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.vn-topbar-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 6px;
  min-width: 0;
  max-width: 100%;
  margin-left: auto;
  flex: 0 1 auto;
  flex-wrap: wrap;
}

.vn-topbar-action,
.vn-topbar-actions > a,
.vn-topbar-actions > button {
  box-sizing: border-box;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 0 11px;
  border: 1px solid transparent;
  border-radius: 8px;
  color: var(--vn-header-action);
  background: transparent;
  font: inherit;
  font-size: 13px;
  line-height: 1.3;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
  transition: background-color 160ms ease, border-color 160ms ease, color 160ms ease, transform 160ms ease;
}

.vn-topbar-action:hover,
.vn-topbar-actions > a:hover,
.vn-topbar-actions > button:hover {
  color: var(--vn-header-text);
  background: var(--vn-header-hover);
  border-color: var(--vn-header-border);
}

.vn-topbar-action:active,
.vn-topbar-actions > a:active,
.vn-topbar-actions > button:active {
  transform: translateY(1px);
}

.vn-topbar-action:focus-visible,
.vn-topbar-actions > a:focus-visible,
.vn-topbar-actions > button:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--vn-header-focus) 42%, transparent);
  outline-offset: 2px;
  border-color: var(--vn-header-focus);
}

.vn-topbar-action:disabled,
.vn-topbar-actions > button:disabled,
.vn-topbar-actions > a[aria-disabled='true'] {
  opacity: 0.52;
  cursor: not-allowed;
  pointer-events: none;
}

.vn-topbar-action.is-primary,
.vn-topbar-actions > .primary,
.vn-topbar-actions > a[data-variant='primary'],
.vn-topbar-actions > button[data-variant='primary'] {
  color: var(--vn-primary-contrast, #ffffff);
  background: var(--vn-header-focus);
  border-color: var(--vn-header-focus);
}

.vn-topbar-action.is-primary:hover,
.vn-topbar-actions > .primary:hover,
.vn-topbar-actions > a[data-variant='primary']:hover,
.vn-topbar-actions > button[data-variant='primary']:hover {
  color: var(--vn-primary-contrast, #ffffff);
  filter: brightness(0.94);
}

.vn-topbar-action.is-icon {
  width: 40px;
  padding: 0;
}

.vn-topbar--overlay {
  position: absolute;
  top: 0;
  left: 0;
  background: color-mix(in srgb, var(--vn-header-bg) 88%, transparent);
}

/* Compatibility styling for retained page-specific header hooks. */
.wiki-header.vn-topbar,
.guide-header.vn-topbar,
.poster-header.vn-topbar,
.admin-topbar.vn-topbar,
.top-header.vn-topbar {
  color: var(--vn-header-action);
}

/* Page-specific shells keep their existing sidebar, breadcrumb and controls,
   while the shared brand remains the only primary header identity. */
.admin-topbar.admin-topbar--manual {
  height: auto;
  min-height: 58px;
  padding: 8px clamp(14px, 3vw, 24px);
  gap: 16px;
}
.admin-topbar.admin-topbar--manual .admin-topbar-leading,
.galonly-top-header.galonly-top-header.vn-topbar .galonly-topbar-leading {
  min-width: 0;
  flex: 1 1 auto;
  gap: 16px;
}
.admin-topbar.admin-topbar--manual .topbar-breadcrumb,
.galonly-top-header.galonly-top-header.vn-topbar .breadcrumb {
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.admin-topbar.admin-topbar--manual .topbar-actions,
.galonly-top-header.galonly-top-header.vn-topbar .header-actions {
  min-width: 0;
  max-width: 100%;
  margin-left: auto;
  flex: 0 1 auto;
  flex-wrap: wrap;
  gap: 6px;
}
.admin-topbar.admin-topbar--manual .topbar-theme-btn,
.galonly-top-header.galonly-top-header.vn-topbar .theme-toggle {
  min-width: 40px;
  min-height: 40px;
}
.admin-topbar.admin-topbar--manual .mobile-menu-btn,
.galonly-top-header.galonly-top-header.vn-topbar .mobile-menu-btn {
  flex: 0 0 auto;
}

.galonly-top-header.galonly-top-header.vn-topbar {
  height: auto;
  min-height: 58px;
  padding: 8px clamp(14px, 3vw, 24px);
  gap: 16px;
}
.galonly-top-header.galonly-top-header.vn-topbar .header-link,
.galonly-top-header.galonly-top-header.vn-topbar .btn-export,
.galonly-top-header.galonly-top-header.vn-topbar .theme-toggle {
  min-height: 40px;
  box-sizing: border-box;
}

.wiki-header.vn-topbar .vn-topbar-brand,
.guide-header.vn-topbar .vn-topbar-brand {
  color: var(--vn-header-text);
}
.wiki-header.vn-topbar .vn-topbar-brand:hover,
.guide-header.vn-topbar .vn-topbar-brand:hover {
  text-decoration: none;
}
.wiki-header.vn-topbar .vn-topbar-actions,
.guide-header.vn-topbar .guide-header-tools {
  flex: 0 1 auto;
  min-width: 0;
  max-width: 100%;
}
.wiki-header.vn-topbar .vn-topbar-actions .wiki-guide-entry {
  margin-left: 0;
}
.guide-header.vn-topbar .guide-header-tools {
  gap: 6px;
}

@media (max-width: 680px) {
  .admin-topbar.admin-topbar--manual,
  .galonly-top-header.galonly-top-header.vn-topbar {
    align-items: flex-start;
    min-height: 60px;
    padding: 8px 12px;
    flex-wrap: wrap;
  }

  .admin-topbar.admin-topbar--manual .admin-topbar-leading,
  .admin-topbar.admin-topbar--manual .topbar-actions,
  .galonly-top-header.galonly-top-header.vn-topbar .galonly-topbar-leading,
  .galonly-top-header.galonly-top-header.vn-topbar .header-actions {
    box-sizing: border-box;
    flex: 1 1 100%;
    width: 100%;
  }
  .admin-topbar.admin-topbar--manual .topbar-actions,
  .galonly-top-header.galonly-top-header.vn-topbar .header-actions {
    justify-content: flex-start;
    margin-left: 0;
  }
  .admin-topbar.admin-topbar--manual .mobile-menu-btn,
  .galonly-top-header.galonly-top-header.vn-topbar .mobile-menu-btn {
    min-width: 44px;
    min-height: 44px;
  }
  .admin-topbar.admin-topbar--manual .topbar-btn span {
    display: none;
  }
  .admin-topbar.admin-topbar--manual .topbar-theme-btn,
  .galonly-top-header.galonly-top-header.vn-topbar .theme-toggle {
    min-width: 44px;
    min-height: 44px;
  }
  .galonly-top-header.galonly-top-header.vn-topbar .header-link:nth-child(2) {
    display: none;
  }
}

@media (max-width: 680px) {
  .vn-topbar {
    align-items: flex-start;
    gap: 8px;
    min-height: 60px;
    padding: 8px 14px;
  }

  .vn-topbar-leading {
    min-height: 44px;
  }

  .vn-topbar-brand {
    min-height: 44px;
  }

  .vn-topbar-actions {
    align-items: stretch;
    gap: 4px;
    flex: 0 1 auto;
  }

  .vn-topbar-action,
  .vn-topbar-actions > a,
  .vn-topbar-actions > button {
    min-height: 44px;
    padding: 0 10px;
  }

  .vn-topbar-action.is-icon {
    width: 44px;
  }
}

@media (max-width: 420px) {
  .vn-topbar {
    flex-wrap: wrap;
  }

  .vn-topbar-leading,
  .vn-topbar-actions {
    flex-basis: 100%;
  }

  .vn-topbar-actions {
    justify-content: flex-start;
    margin-left: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .vn-topbar-action,
  .vn-topbar-actions > a,
  .vn-topbar-actions > button {
    transition: none;
  }

  .vn-topbar-action:active,
  .vn-topbar-actions > a:active,
  .vn-topbar-actions > button:active {
    transform: none;
  }
}