/**
 * Browser component (Brief 85) — view-switcher substrate.
 *
 * Composes existing atoms (.pg-view-toggle, .ds-search, .s-pill-filter) into
 * a unified header strip + body (scroll container + marker rail + lasso
 * layer + live-update pill).
 *
 * Tokens declared in admin-tokens.css under `--browser-*`.
 */

.browser {
  display: flex;
  flex-direction: column;
  height: 100%;
  min-height: 0;
  min-width: 0;
  width: 100%;
  position: relative;
}

/* ── Header ───────────────────────────────────────────────────── */

.browser-header {
  display: flex;
  align-items: center;
  gap: var(--s-space-3);
  padding: var(--s-space-2) var(--s-space-3);
  border-bottom: 1px solid var(--s-color-border);
  background: var(--s-color-bg-app);
  flex-shrink: 0;
  min-height: var(--browser-header-h);
}

.browser-header__left {
  display: flex;
  align-items: center;
  gap: var(--s-space-2);
  flex: 1 1 auto;
  min-width: 0;
}

.browser-header__center {
  flex: 0 0 auto;
  font-size: var(--s-font-size-1);
  color: var(--s-color-fg-muted);
  white-space: nowrap;
  margin: 0 var(--s-space-2);
}

.browser-header__count-num {
  color: var(--s-color-fg-primary);
  font-variant-numeric: tabular-nums;
  font-weight: var(--s-font-weight-semibold);
}

.browser-header__count-unit {
  color: var(--s-color-fg-muted);
}

.browser-header__right {
  display: flex;
  align-items: center;
  gap: var(--s-space-2);
  flex: 0 0 auto;
}

.browser-header__search {
  min-width: 180px;
  max-width: 320px;
  flex: 1 1 240px;
}

.browser-header__filter {
  flex: 0 1 auto;
  overflow-x: auto;
  max-width: 50%;
}

.browser-header__jump {
  display: inline-flex;
  align-items: center;
  gap: var(--s-space-twohair);
  font-size: var(--s-font-size-1);
  color: var(--s-color-fg-muted);
}

.browser-header__jump-input {
  width: 5.5rem;
  padding: var(--s-space-twohair) var(--s-space-2);
  border: 1px solid var(--s-color-border-subtle);
  border-radius: var(--s-radius-1);
  background: var(--s-color-bg-app);
  color: var(--s-color-fg-primary);
  font-family: var(--s-font-mono);
  font-size: var(--s-font-size-1);
}

.browser-header__jump-input:focus {
  outline: 2px solid var(--s-color-accent-default);
  outline-offset: 1px;
}

.browser-header__toggle {
  display: inline-flex;
  align-items: center;
  flex: 0 0 auto;
}

/* ── Body ─────────────────────────────────────────────────────── */

.browser-body-wrap {
  position: relative;
  flex: 1 1 auto;
  min-height: 0;
  display: flex;
}

.browser-body {
  flex: 1 1 auto;
  position: relative;
  overflow: auto;
  outline: none;
  /* Reserve marker-rail width so content doesn't reflow when rail toggles. */
  padding-right: var(--browser-marker-rail-w);
}

.browser-body:focus-visible {
  /* Focus ring on the scroll container itself for keyboard nav. */
  box-shadow: none;
}

.browser-content {
  position: relative;
  /* The virtualizer mounts an absolutely-positioned `.browser-virtualizer`
     child here; naive renders use grid/list/table directly. */
}

.browser-content[data-mode="grid"] .browser-grid,
.browser-content[data-mode="grid"] .browser-virtualizer {
  /* Grid mode wraps via flex-wrap when not virtualized; virtualizer
     positions cards absolutely and computes column count itself. */
}

/* Naive grid render — flex-wrap / flex-grid for ≤3000 items. */
.browser-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  padding: var(--s-space-3);
  align-content: flex-start;
}

.browser-card {
  flex: 0 0 200px;
  min-height: var(--browser-item-h, 180px);
  padding: var(--s-space-3);
  border: 1px solid var(--s-color-border-subtle);
  border-radius: var(--s-radius-2);
  background: var(--s-color-bg-app);
  cursor: pointer;
  transition:
    border-color 0.12s,
    box-shadow 0.12s,
    background 0.12s;
  user-select: none;
}

.browser-card:hover {
  border-color: var(--s-color-border);
  box-shadow: none;
}

.browser-card.is-selected {
  border-color: var(--s-color-accent-default);
  background: color-mix(in oklch, var(--s-color-accent-default) 10%, var(--s-color-bg-app));
  box-shadow: none;
}

/* Keyboard-nav active cursor (GH #265). Distinct from selection — the
   active item is where the keyboard cursor lives; Enter activates it
   (same effect as a click). Outline-based so it stacks cleanly on top
   of selection styling without clobbering it. */
.browser-card.is-active,
.browser-card[data-active="true"] {
  outline: 2px solid var(--s-color-accent-default);
  outline-offset: -2px;
}

.browser-card__title {
  font-weight: var(--s-font-weight-semibold);
  color: var(--s-color-fg-primary);
  font-size: var(--s-font-size-1);
}

.browser-card__meta {
  font-size: var(--s-font-size-0);
  color: var(--s-color-fg-muted);
  margin-top: var(--s-space-1);
}

/* Naive list render. */
.browser-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
}

.browser-list__row {
  padding: var(--s-space-2) var(--s-space-3);
  border-bottom: 1px solid var(--s-color-border-subtle);
  cursor: pointer;
  display: flex;
  align-items: center;
  min-height: var(--browser-item-h, 56px);
  user-select: none;
}

.browser-list__row:hover {
  background: var(--s-color-hover-bg);
}

.browser-list__row.is-selected {
  background: color-mix(in oklch, var(--s-color-accent-default) 12%, var(--s-color-bg-app));
  border-left: 3px solid var(--s-color-accent-default);
  padding-left: calc(var(--s-space-3) - 3px);
}

.browser-list__row.is-active,
.browser-list__row[data-active="true"] {
  outline: 2px solid var(--s-color-accent-default);
  outline-offset: -2px;
}

/* Phase B — content-visibility band (501-3000 items). Engines skip
   layout/paint of off-screen items while preserving correct scroll math
   via contain-intrinsic-size. */
.browser-cv-auto {
  content-visibility: auto;
  contain-intrinsic-size: auto var(--browser-item-h, 80px);
}

/* Skeleton placeholder — used during initial paint when consumer renders
   a card via opts.cardRenderer that returns a delayed/asynchronous shape.
   CSS-only animation so no JS overhead. */
.browser-skeleton {
  animation: browser-skeleton-pulse 1.4s ease-in-out infinite;
  background: var(--s-color-bg-subtle);
  border-radius: var(--s-radius-1);
  min-height: 12px;
}

@keyframes browser-skeleton-pulse {
  0%,
  100% {
    opacity: 0.5;
  }
  50% {
    opacity: 0.85;
  }
}

/* Naive/fallback table. */
.browser-table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--s-font-size-1);
  user-select: none;
}

.browser-table thead th {
  text-align: start;
  padding: var(--s-space-2) var(--s-space-3);
  font-weight: var(--s-font-weight-semibold);
  color: var(--s-color-fg-muted);
  background: var(--s-color-bg-subtle);
  border-bottom: 1px solid var(--s-color-border);
  position: sticky;
  top: 0;
  z-index: 1;
}

.browser-table tbody td {
  padding: var(--s-space-2) var(--s-space-3);
  border-bottom: 1px solid var(--s-color-border-subtle);
  color: var(--s-color-fg-primary);
}

.browser-table tbody tr {
  cursor: pointer;
}

.browser-table tbody tr:hover {
  background: var(--s-color-hover-bg);
}

.browser-table tbody tr.is-selected {
  background: color-mix(in oklch, var(--s-color-accent-default) 14%, var(--s-color-bg-app));
}

.browser-table tbody tr.is-active,
.browser-table tbody tr[data-active="true"] {
  outline: 2px solid var(--s-color-accent-default);
  outline-offset: -2px;
}

/* Empty state. */
.browser-empty {
  padding: var(--s-space-6) var(--s-space-3);
  text-align: center;
  color: var(--s-color-fg-muted);
}

.browser-empty__title {
  font-size: var(--s-font-size-2);
  font-weight: var(--s-font-weight-semibold);
  color: var(--s-color-fg-primary);
}

.browser-empty__desc {
  margin-top: var(--s-space-2);
  font-size: var(--s-font-size-1);
}

/* a11y match announcer — hidden visually, announced by SR via aria-live. */
.browser-announcer {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ── Live update pill ─────────────────────────────────────────── */

.browser-live-pill {
  position: sticky;
  top: var(--s-space-2);
  align-self: center;
  z-index: 4;
  margin: var(--s-space-2) auto 0;
  padding: var(--s-space-twohair) var(--s-space-3);
  background: var(--browser-pill-bg);
  color: var(--browser-pill-fg);
  border: none;
  border-radius: 999px;
  font-size: var(--s-font-size-0);
  font-weight: var(--s-font-weight-semibold);
  cursor: pointer;
  box-shadow: none;
  display: block;
  transition:
    transform 0.18s ease,
    opacity 0.18s ease;
}

.browser-live-pill[hidden] {
  display: none;
}

.browser-live-pill:hover {
  transform: translateY(-1px);
  opacity: 0.95;
}

/* ── Marker rail ──────────────────────────────────────────────── */

.browser-marker-rail {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  /* width is set inline by the rail JS to ensure it resolves to 12-16px
     reliably regardless of cascade order. */
  background: transparent;
  pointer-events: auto;
  z-index: 3;
}

.browser-marker-rail__track {
  position: absolute;
  inset: 0;
}

.browser-marker {
  position: absolute;
  left: 1px;
  right: 1px;
  border-radius: 1px;
  cursor: pointer;
}

.browser-marker--hit {
  background: var(--browser-marker-hit);
}

.browser-marker--selected {
  background: var(--browser-marker-selected);
}

.browser-marker--both {
  background: var(--browser-marker-both);
}

.browser-marker-rail__viewport {
  position: absolute;
  left: 0;
  right: 0;
  background: var(--browser-marker-viewport);
  pointer-events: none;
  border-radius: 2px;
}

/* ── Lasso layer ──────────────────────────────────────────────── */

.browser-lasso-layer {
  /* Most styling is set inline by the lasso JS (position:absolute;
     pointer-events: none default). */
}

.browser-lasso-rect {
  background: var(--browser-lasso-bg);
  border: 1px solid var(--browser-lasso-border);
  pointer-events: none;
}

/* ── Virtualizer host ─────────────────────────────────────────── */

.browser-virtualizer {
  /* The virtualizer JS sets height/position. This selector is a hook for
     future tuning (e.g., per-mode padding). */
}

/* When the virtualizer is active, ensure cards/rows don't have flex layout
   conflicts (virtualizer absolutely-positions them). */
.browser-virtualizer > .browser-card,
.browser-virtualizer > .browser-list__row {
  /* `position: absolute` is set inline by the virtualizer; we just clean
     up any flex overrides the naive paths set. */
  margin: 0;
  flex: none;
}