/* PR preview overlay (FR-3879): change marks, hover diff, navigator. */
:root {
  --bai-add: #16a34a;
  --bai-add-bg: rgba(34, 197, 94, 0.18);
  --bai-mod: #ca8a04;
  --bai-mod-bg: rgba(250, 204, 21, 0.32);
  --bai-del: #dc2626;
  --bai-del-bg: rgba(239, 68, 68, 0.14);
  --bai-del-fg: #dc2626;
  --bai-ins-bg: rgba(34, 197, 94, 0.22);
  --bai-ins-fg: #16a34a;
  --bai-pop-bg: #fff;
  --bai-pop-fg: #111827;
  --bai-pop-border: #d1d5db;
  --bai-focus: #2563eb;
  --bai-accent: #ff7a00;
  --bai-viewed-line: rgba(107, 114, 128, 0.55);
  --bai-viewed-badge: #6b7280;
  --bai-row-hover: rgba(37, 99, 235, 0.08);
}
[data-theme="dark"] {
  --bai-mod-bg: rgba(250, 204, 21, 0.22);
  --bai-add-bg: rgba(34, 197, 94, 0.22);
  --bai-del-fg: #fca5a5;
  --bai-ins-fg: #86efac;
  --bai-pop-bg: #1f2937;
  --bai-pop-fg: #f3f4f6;
  --bai-pop-border: #4b5563;
  --bai-row-hover: rgba(96, 165, 250, 0.16);
}

/* ---------- word-level diff ---------- */
.bai-del {
  background: var(--bai-del-bg);
  color: var(--bai-del-fg);
  text-decoration: line-through;
  text-decoration-thickness: 1.5px;
  border-radius: 2px;
}
.bai-ins {
  background: var(--bai-ins-bg);
  color: var(--bai-ins-fg);
  text-decoration: underline;
  text-decoration-thickness: 1.5px;
  border-radius: 2px;
}

/* ---------- marks ---------- */
[data-bai-change] { position: relative; }
.bai-pr-preview [data-bai-change][data-bai-type="modified"],
.bai-pr-preview [data-bai-change][data-bai-type="added"] {
  background: var(--bai-mod-bg);
  box-shadow: 0 0 0 4px var(--bai-mod-bg);
  outline: 1.5px dashed var(--bai-accent);
  outline-offset: 5px;
  border-radius: 3px;
  cursor: help;
}
.bai-pr-preview [data-bai-change][data-bai-type="added"] {
  background: var(--bai-add-bg);
  box-shadow: 0 0 0 4px var(--bai-add-bg);
}
/* Shrink-wrap the highlight to the image but keep the figure centered like
   the published page (inline-block left-aligned narrow images). */
.bai-pr-preview figure[data-bai-change] {
  display: block;
  width: fit-content;
  max-width: 100%;
  margin-inline: auto;
  padding: 4px;
}
.bai-pr-preview .bai-removed-placeholder {
  border: 1.5px dashed var(--bai-del);
  background: var(--bai-del-bg);
  color: var(--bai-del-fg);
  border-radius: 4px;
  padding: 4px 10px;
  margin: 6px 0;
  font-size: 0.85em;
  cursor: help;
}
.bai-pr-preview .bai-removed-placeholder::before {
  content: "− removed: ";
  font-weight: 600;
}
.bai-pr-preview .bai-removed-placeholder .bai-removed-text {
  opacity: 0.8;
  text-decoration: line-through;
}

/* viewed: the mark recedes to a faint dashed frame with a check badge */
.bai-pr-preview [data-bai-change].bai-viewed[data-bai-type="modified"],
.bai-pr-preview [data-bai-change].bai-viewed[data-bai-type="added"] {
  background: transparent;
  box-shadow: none;
  outline: 1.5px dashed var(--bai-viewed-line);
}
.bai-pr-preview .bai-removed-placeholder.bai-viewed {
  border-color: var(--bai-viewed-line);
  background: transparent;
  color: var(--bai-viewed-line);
}
.bai-pr-preview [data-bai-change].bai-viewed::after {
  content: "✓ viewed";
  position: absolute;
  top: -12px;
  right: -6px;
  font: 600 10px/1 system-ui, sans-serif;
  letter-spacing: 0.02em;
  color: #fff;
  background: var(--bai-viewed-badge);
  padding: 2px 6px;
  border-radius: 999px;
  pointer-events: none;
}

/* commented: the same badge in the accent colour; both states share it */
.bai-pr-preview [data-bai-change].bai-commented::after {
  content: "✎ comment";
  position: absolute;
  top: -12px;
  right: -6px;
  font: 600 10px/1 system-ui, sans-serif;
  letter-spacing: 0.02em;
  color: #fff;
  background: var(--bai-focus);
  padding: 2px 6px;
  border-radius: 999px;
  pointer-events: none;
}
.bai-pr-preview [data-bai-change].bai-viewed.bai-commented::after {
  content: "✓ viewed · ✎ comment";
  background: var(--bai-focus);
}

/* ---------- marks hidden ---------- */
.bai-marks-off [data-bai-change] {
  background: none !important;
  box-shadow: none !important;
  outline: none !important;
  cursor: auto;
}
.bai-marks-off [data-bai-change].bai-viewed::after,
.bai-marks-off [data-bai-change].bai-commented::after { content: none; }
.bai-marks-off .bai-removed-placeholder { display: none !important; }

/* Marks are reachable by Tab, so the focus ring must beat `marks off`. */
.bai-pr-preview [data-bai-change]:focus-visible {
  outline: 3px solid var(--bai-focus) !important;
  outline-offset: 4px !important;
}

/* ---------- focus flash (navigator jump) ---------- */
.bai-flash {
  outline: 3px solid var(--bai-focus);
  outline-offset: 4px;
  transition: outline-color 1.2s ease;
}
.bai-flash.bai-flash--fade { outline-color: transparent; }

/* ---------- hover popover ---------- */
.bai-popover {
  position: fixed;
  z-index: 9000;
  max-width: min(720px, 92vw);
  background: var(--bai-pop-bg);
  color: var(--bai-pop-fg);
  border: 1px solid var(--bai-pop-border);
  border-radius: 8px;
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.22);
  font-size: 13px;
  line-height: 1.5;
}
.bai-popover[hidden] { display: none; }
.bai-popover__head {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 10px;
  border-bottom: 1px solid var(--bai-pop-border);
  font-size: 12px;
}
.bai-popover__type {
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}
.bai-popover__type--added { color: var(--bai-add); }
.bai-popover__type--modified { color: var(--bai-mod); }
.bai-popover__type--removed { color: var(--bai-del); }
.bai-popover__kind { opacity: 0.7; }
.bai-popover__spacer { flex: 1; }
.bai-popover__mode {
  display: inline-flex;
  border: 1px solid var(--bai-pop-border);
  border-radius: 4px;
  overflow: hidden;
}
.bai-popover__mode button {
  border: 0;
  background: transparent;
  color: inherit;
  padding: 2px 8px;
  font: inherit;
  font-size: 11px;
  cursor: pointer;
}
.bai-popover__mode button[aria-pressed="true"] {
  background: var(--bai-focus);
  color: #fff;
}
.bai-popover__btn {
  border: 1px solid var(--bai-pop-border);
  background: transparent;
  color: inherit;
  border-radius: 4px;
  padding: 2px 8px;
  font: inherit;
  font-size: 11px;
  cursor: pointer;
  white-space: nowrap;
}
.bai-popover__btn:hover { border-color: var(--bai-focus); color: var(--bai-focus); }
.bai-popover__btn.bai-copied,
.bai-nav__actions button.bai-copied {
  background: var(--bai-add);
  border-color: var(--bai-add);
  color: #fff;
}
.bai-popover__viewed {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 11px;
  cursor: pointer;
  white-space: nowrap;
  user-select: none;
}
.bai-popover__viewed input { margin: 0; accent-color: var(--bai-add); }
.bai-popover__comment { padding: 8px 12px 0; }
.bai-popover__comment textarea {
  display: block;
  width: 100%;
  box-sizing: border-box;
  min-height: 28px;
  max-height: 160px;
  resize: none;
  overflow-y: auto;
  border: 1px solid var(--bai-pop-border);
  border-radius: 4px;
  background: transparent;
  color: inherit;
  font: inherit;
  font-size: 12px;
  line-height: 1.4;
  padding: 4px 8px;
}
.bai-popover__comment textarea::placeholder { opacity: 0.55; }
.bai-popover__comment textarea:not(:placeholder-shown) { border-color: var(--bai-focus); }
.bai-popover__comment textarea:focus {
  outline: none;
  border-color: var(--bai-focus);
  box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.25);
}
.bai-popover__where {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  margin-right: 10px;
  opacity: 0.9;
}
.bai-popover__hint kbd {
  border: 1px solid var(--bai-pop-border);
  border-radius: 3px;
  padding: 0 4px;
  font-size: 10px;
}
.bai-popover__body { padding: 10px 12px; max-height: 60vh; overflow: auto; }
.bai-popover__body p { margin: 0; }
.bai-popover__body img { max-width: 100%; height: auto; }
.bai-popover__body table { border-collapse: collapse; }
.bai-popover__body td,
.bai-popover__body th {
  border: 1px solid var(--bai-pop-border);
  padding: 2px 6px;
}
.bai-popover__sbs { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.bai-popover__sbs--single { grid-template-columns: 1fr; }
.bai-popover__sbs > div { min-width: 0; }
.bai-popover__sbs .bai-col-label {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  opacity: 0.6;
  margin-bottom: 4px;
}
.bai-popover__sbs .bai-col--old {
  border-left: 3px solid var(--bai-del);
  padding-left: 8px;
}
.bai-popover__sbs .bai-col--new {
  border-left: 3px solid var(--bai-add);
  padding-left: 8px;
}
.bai-popover__caption {
  margin-top: 8px;
  padding-top: 6px;
  border-top: 1px solid var(--bai-pop-border);
  font-size: 12px;
}
.bai-popover__mode button[disabled] { opacity: 0.45; cursor: default; }
.bai-popover__img {
  cursor: zoom-in;
  border: 1px solid var(--bai-pop-border);
  border-radius: 4px;
}
.bai-popover__hint { padding: 4px 12px 8px; font-size: 11px; opacity: 0.6; }

/* ---------- shortcut toast ---------- */
.bai-toast {
  position: fixed;
  left: 50%;
  bottom: 64px;
  transform: translateX(-50%);
  z-index: 9200;
  background: var(--bai-pop-fg);
  color: var(--bai-pop-bg);
  font: 12px/1 system-ui, sans-serif;
  padding: 6px 12px;
  border-radius: 999px;
  pointer-events: none;
}
.bai-toast[hidden] { display: none; }

/* ---------- lightbox ---------- */
.bai-lightbox {
  position: fixed;
  inset: 0;
  z-index: 9500;
  background: rgba(0, 0, 0, 0.82);
  display: grid;
  place-items: center;
  cursor: zoom-out;
}
.bai-lightbox__pair {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  max-width: 96vw;
}
.bai-lightbox__pair img {
  max-width: 47vw;
  max-height: 88vh;
  object-fit: contain;
  background: #fff;
}
.bai-lightbox__pair div {
  color: #fff;
  text-align: center;
  font: 600 12px system-ui, sans-serif;
  text-transform: uppercase;
}
.bai-lightbox__pair div:first-child img { outline: 3px solid var(--bai-del); }
.bai-lightbox__pair div:last-child img { outline: 3px solid var(--bai-add); }

/* ---------- change navigator ---------- */
.bai-nav {
  position: fixed;
  right: 20px;
  bottom: 20px;
  z-index: 8800;
  font: 13px/1.4 system-ui, -apple-system, sans-serif;
  color: var(--bai-pop-fg);
}
.bai-nav__badge {
  display: flex;
  align-items: center;
  gap: 6px;
  background: var(--bai-pop-bg);
  border: 1px solid var(--bai-pop-border);
  border-radius: 999px;
  padding: 6px 8px 6px 14px;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.18);
}
.bai-nav__badge strong { font-weight: 700; }
.bai-nav__badge button {
  border: 1px solid var(--bai-pop-border);
  background: transparent;
  color: inherit;
  border-radius: 999px;
  width: 26px;
  height: 26px;
  cursor: pointer;
  font-size: 13px;
  line-height: 1;
}
.bai-nav__badge button:hover {
  background: var(--bai-focus);
  color: #fff;
  border-color: var(--bai-focus);
}
.bai-nav__badge button.bai-nav__comments {
  width: auto;
  padding: 0 10px;
  font-size: 12px;
  white-space: nowrap;
  border-color: var(--bai-focus);
  color: var(--bai-focus);
}
.bai-nav__badge button.bai-nav__comments:hover {
  background: var(--bai-focus);
  color: #fff;
}
.bai-nav__badge button.bai-nav__comments[hidden] { display: none; }
.bai-nav__badge button.bai-nav__comments.bai-copied {
  background: var(--bai-add);
  border-color: var(--bai-add);
  color: #fff;
}
.bai-nav__pos {
  min-width: 5.5em;
  text-align: center;
  opacity: 0.75;
  font-variant-numeric: tabular-nums;
}
.bai-nav__pos--done { color: var(--bai-add); font-weight: 600; opacity: 1; }
.bai-nav__panel {
  position: absolute;
  right: 0;
  bottom: 44px;
  width: 360px;
  max-height: 60vh;
  overflow: auto;
  background: var(--bai-pop-bg);
  border: 1px solid var(--bai-pop-border);
  border-radius: 10px;
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.22);
  padding: 8px 0;
}
.bai-nav__panel[hidden] { display: none; }
.bai-nav__section {
  padding: 6px 14px 4px;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  opacity: 0.6;
}
.bai-nav__row {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 5px 14px;
  text-decoration: none;
  color: inherit;
}
a.bai-nav__row:hover { background: var(--bai-row-hover); }
.bai-nav__row--current { font-weight: 700; }
.bai-nav__row--deleted { text-decoration: line-through; opacity: 0.7; }
.bai-nav__row .bai-nav__title {
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.bai-nav__count {
  font-size: 11px;
  padding: 1px 7px;
  border-radius: 999px;
  background: var(--bai-mod-bg);
  color: var(--bai-pop-fg);
  font-variant-numeric: tabular-nums;
}
.bai-nav__count--done { background: var(--bai-add); color: #fff; }
.bai-nav__count--note { background: var(--bai-focus); color: #fff; }
/* the pins of one page, listed under its row */
.bai-nav__pins { margin: 0 14px 4px 22px; border-left: 1px solid var(--bai-pop-border); }
.bai-nav__pin {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 3px 6px 3px 8px;
  font-size: 12px;
  text-decoration: none;
  color: inherit;
}
a.bai-nav__pin:hover { background: var(--bai-row-hover); }
.bai-nav__pin--viewed { opacity: 0.55; }
.bai-nav__pin--empty { opacity: 0.6; font-style: italic; }
.bai-nav__pin-id {
  flex: none;
  min-width: 18px;
  text-align: center;
  font: 700 10px/15px system-ui, sans-serif;
  border-radius: 3px;
  color: #fff;
  font-variant-numeric: tabular-nums;
  background: var(--bai-mod);
}
.bai-nav__pin-id--added { background: var(--bai-add); }
.bai-nav__pin-id--removed { background: var(--bai-del); }
.bai-nav__pin-text {
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.bai-nav__pin-flag { flex: none; font-size: 11px; opacity: 0.8; }
.bai-nav__pin-flag--note { color: var(--bai-focus); opacity: 1; }
.bai-nav__actions {
  display: flex;
  gap: 6px;
  padding: 8px 14px 4px;
  flex-wrap: wrap;
}
.bai-nav__actions button {
  border: 1px solid var(--bai-pop-border);
  background: transparent;
  color: inherit;
  border-radius: 999px;
  padding: 3px 10px;
  font: inherit;
  font-size: 11px;
  cursor: pointer;
}
.bai-nav__actions button:hover { border-color: var(--bai-focus); color: var(--bai-focus); }
.bai-nav__stale {
  margin: 6px 14px 0;
  padding: 6px 10px;
  border-radius: 6px;
  background: var(--bai-mod-bg);
  font-size: 11.5px;
}
.bai-nav__tag {
  font-size: 10px;
  font-weight: 700;
  padding: 1px 6px;
  border-radius: 3px;
  color: #fff;
}
.bai-nav__tag--new { background: var(--bai-add); }
.bai-nav__tag--deleted { background: var(--bai-del); }
.bai-nav__lang { display: flex; gap: 6px; padding: 4px 14px 8px; flex-wrap: wrap; }
.bai-nav__lang a {
  font-size: 12px;
  padding: 2px 8px;
  border-radius: 999px;
  border: 1px solid var(--bai-pop-border);
  text-decoration: none;
  color: inherit;
}
.bai-nav__lang a.bai-nav__lang--current {
  background: var(--bai-focus);
  color: #fff;
  border-color: var(--bai-focus);
}

/* ---------- sidebar page badges ---------- */
.bai-nav-badge {
  display: inline-block;
  margin-left: 6px;
  font-size: 10px;
  font-weight: 700;
  padding: 0 6px;
  border-radius: 999px;
  background: var(--bai-mod-bg);
  color: inherit;
  vertical-align: middle;
  font-variant-numeric: tabular-nums;
}
.bai-nav-badge--new { background: var(--bai-add); color: #fff; }
.bai-nav-badge--deleted { background: var(--bai-del); color: #fff; }

/* ---------- new / deleted page banner ---------- */
.bai-page-banner {
  margin: 0 0 16px;
  padding: 8px 12px;
  border-radius: 6px;
  border: 1px solid var(--bai-add);
  background: var(--bai-add-bg);
  font-size: 13px;
}
.bai-page-banner--deleted {
  border-color: var(--bai-del);
  background: var(--bai-del-bg);
}
.bai-page-banner .bai-nav__tag { margin-right: 6px; }