/* ============================================
   xm-multi-select — multiple-value picker for XmField (Component-Capability
   Epic 2, ADR 0014).

   Composes XmField (chrome) + xm-overlay (anchored panel) + xm-checkbox (the
   per-option selected indicator) + xm-text-field (search). This file styles ONLY
   the bespoke parts: the closed trigger (a full-bleed <button> inside the base's
   .field__control wrapper), the chevron, and the panel content (search + listbox)
   projected into the overlay. Positioning / elevation of the panel is owned by
   xm-overlay; the option checkbox visual is owned by xm-checkbox.

   Surface & ink (AD-13):
     • Closed trigger rides the inverse-surface card tier → inverse-on-surface ink,
       inverse-on-surface-muted for the placeholder.
     • The panel rows sit on the overlay's inverse-surface panel → ink stays
       inverse-on-surface; hover/active uses the MD3 state layer.
     • Selection is carried by the row's xm-checkbox (coral fill), NOT a row tint —
       so the active (keyboard/hover) highlight never double-signals with selection.

   BEM block: `multi-select`. Registered in scripts/check-bem.sh STRICT_BLOCKS.
   ============================================ */

/* ---------- Closed trigger — full-bleed button in the field wrapper ---------- */
.multi-select__control {
  position: relative;
  display: flex;
  align-items: center;
  gap: var(--s-2);
  flex: 1;
  min-width: 0;
  width: 100%;
  height: 100%;
  box-sizing: border-box;
  appearance: none;
  border: none;
  outline: none;
  background: transparent;
  color: var(--md-sys-color-inverse-on-surface);
  font:
    var(--md-sys-typescale-body-large-weight)
    var(--md-sys-typescale-body-large-size) /
    var(--md-sys-typescale-body-large-line-height)
    var(--md-sys-typescale-body-large-font);
  padding: 0 var(--s-3);
  text-align: left;
  cursor: pointer;
}
.multi-select__control--disabled {
  cursor: not-allowed;
}

/* ---------- Value / placeholder ---------- */
.multi-select__value {
  flex: 1;
  min-width: 0;
  display: flex;
  align-items: center;
  gap: var(--s-1);
  overflow: hidden;
  white-space: nowrap;
}
.multi-select__placeholder {
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  color: var(--xm-color-inverse-on-surface-muted);
}

.multi-select__chip {
  display: inline-flex;
  align-items: center;
  gap: var(--s-0-5);
  min-width: 0;
  max-width: 100%;
  flex-shrink: 1;
  box-sizing: border-box;
  padding: var(--s-0-5) var(--s-1);
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--md-sys-shape-corner-small);
  color: var(--md-sys-color-inverse-on-surface);
  font:
    var(--md-sys-typescale-label-medium-weight)
    var(--md-sys-typescale-label-medium-size) /
    var(--md-sys-typescale-label-medium-line-height)
    var(--md-sys-typescale-label-medium-font);
}
.multi-select__chip-label {
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
}
.multi-select__chip-remove {
  display: inline-flex;
  align-items: center;
  flex-shrink: 0;
  border-radius: var(--md-sys-shape-corner-full);
  color: var(--xm-color-inverse-on-surface-muted);
  cursor: pointer;
  transition: color var(--md-sys-motion-duration-short3)
    var(--md-sys-motion-easing-standard);
}
.multi-select__chip-remove:hover {
  color: var(--md-sys-color-inverse-on-surface);
}
.multi-select__chip--overflow {
  flex-shrink: 0;
  color: var(--xm-color-inverse-on-surface-muted);
  font-variant-numeric: tabular-nums;
}

.multi-select__measure {
  position: absolute;
  top: 0;
  left: 0;
  display: flex;
  align-items: center;
  gap: var(--s-1);
  visibility: hidden;
  pointer-events: none;
  white-space: nowrap;
}

/* ---------- Chevron — rotates on open (short3, standard) ---------- */
.multi-select__chevron {
  display: inline-flex;
  align-items: center;
  flex-shrink: 0;
  color: var(--md-sys-color-inverse-on-surface);
  transition: transform var(--md-sys-motion-duration-short3)
    var(--md-sys-motion-easing-standard);
}
.multi-select__chevron--open {
  transform: rotate(180deg);
}

/* ---------- Panel (inside the overlay): search + listbox ---------- */
.multi-select__panel {
  display: flex;
  flex-direction: column;
  gap: var(--s-2);
}
.multi-select__search {
  display: block;
  width: 100%;
  --xm-field-control-pad-x: var(--s-2);
}

/* ---------- Listbox ---------- */
.multi-select__listbox {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: var(--s-0-5);
  max-height: 280px;
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: var(--xm-scrollbar-thumb-inverse) transparent;
}
.multi-select__listbox:focus {
  outline: none;
}
.multi-select__listbox::-webkit-scrollbar {
  width: var(--s-scrollbar-w);
}
.multi-select__listbox::-webkit-scrollbar-track {
  background: transparent;
}
.multi-select__listbox::-webkit-scrollbar-thumb {
  background: var(--xm-scrollbar-thumb-inverse);
  border-radius: var(--md-sys-shape-corner-full);
  border: 2px solid transparent;
  background-clip: content-box;
}
.multi-select__listbox::-webkit-scrollbar-thumb:hover {
  background: var(--xm-scrollbar-thumb-inverse-hover);
  background-clip: content-box;
}

/* ---------- Option rows ---------- */
.multi-select__option {
  display: flex;
  align-items: center;
  gap: var(--s-2);
  padding: var(--s-1) var(--s-2);
  border-radius: var(--md-sys-shape-corner-small);
  color: var(--md-sys-color-inverse-on-surface);
  font:
    var(--md-sys-typescale-body-medium-weight)
    var(--md-sys-typescale-body-medium-size) /
    var(--md-sys-typescale-body-medium-line-height)
    var(--md-sys-typescale-body-medium-font);
  cursor: pointer;
  user-select: none;
  transition: opacity var(--md-sys-motion-duration-short4)
    var(--md-sys-motion-easing-standard);
}
.multi-select__listbox--loading .multi-select__option,
.multi-select__listbox--loading .multi-select__group-label {
  opacity: 0.45;
}
.multi-select__listbox--loading .multi-select__option {
  cursor: progress;
}
.multi-select__group-label,
.multi-select__group-separator,
.multi-select__empty {
  transition: opacity var(--md-sys-motion-duration-short4)
    var(--md-sys-motion-easing-standard);
}
.multi-select__option-label {
  flex: 1;
  min-width: 0;
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
}

/* The option checkbox is presentational — the row owns the click + a11y. */
.multi-select__check {
  flex-shrink: 0;
  pointer-events: none;
}

/* Active (keyboard / pointer hover) — the MD3 state layer over the panel ink. */
.multi-select__option--active {
  background: color-mix(
    in oklab,
    var(--md-sys-color-inverse-on-surface)
      var(--md-sys-state-hover-state-layer-opacity),
    transparent
  );
}

/* Disabled option (explicitly disabled, or unselected at the `max` cap). */
.multi-select__option--disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.multi-select__option-meta {
  flex-shrink: 0;
  color: var(--xm-color-inverse-on-surface-muted);
  font:
    var(--md-sys-typescale-body-small-weight)
    var(--md-sys-typescale-body-small-size) /
    var(--md-sys-typescale-body-small-line-height)
    var(--md-sys-typescale-body-small-font);
  font-variant-numeric: tabular-nums;
}

.multi-select__bulk {
  display: flex;
  align-items: center;
  gap: var(--s-1);
}
.multi-select__bulk-btn {
  appearance: none;
  border: none;
  background: transparent;
  padding: var(--s-0-5) var(--s-1);
  border-radius: var(--md-sys-shape-corner-small);
  color: var(--md-sys-color-inverse-on-surface);
  font:
    var(--md-sys-typescale-label-medium-weight)
    var(--md-sys-typescale-label-medium-size) /
    var(--md-sys-typescale-label-medium-line-height)
    var(--md-sys-typescale-label-medium-font);
  cursor: pointer;
  transition: background var(--md-sys-motion-duration-short3)
    var(--md-sys-motion-easing-standard);
}
.multi-select__bulk-btn:hover {
  background: color-mix(
    in oklab,
    var(--md-sys-color-inverse-on-surface)
      var(--md-sys-state-hover-state-layer-opacity),
    transparent
  );
}
.multi-select__bulk-btn:focus {
  outline: none;
}
.multi-select__bulk-btn:focus-visible {
  outline: none;
  box-shadow: var(--xm-state-focus-ring);
}

.multi-select__group-label {
  list-style: none;
  padding: var(--s-1) var(--s-2) var(--s-0-5);
  color: var(--xm-color-inverse-on-surface-muted);
  font:
    var(--md-sys-typescale-label-small-weight)
    var(--md-sys-typescale-label-small-size) /
    var(--md-sys-typescale-label-small-line-height)
    var(--md-sys-typescale-label-small-font);
  letter-spacing: var(--md-sys-typescale-label-small-tracking);
}
.multi-select__group-separator {
  list-style: none;
  height: 1px;
  margin: var(--s-1) var(--s-2);
  background: var(--md-sys-color-outline-variant);
}

.multi-select__note {
  display: flex;
  align-items: flex-start;
  gap: var(--s-1-5);
  padding: var(--s-1) var(--s-2) 0;
  color: var(--xm-color-inverse-on-surface-muted);
  font:
    var(--md-sys-typescale-body-small-weight)
    var(--md-sys-typescale-body-small-size) /
    var(--md-sys-typescale-body-small-line-height)
    var(--md-sys-typescale-body-small-font);
}
.multi-select__note:empty {
  display: none;
}
.multi-select__note-icon {
  flex-shrink: 0;
}

.multi-select__spacer {
  list-style: none;
  flex-shrink: 0;
}

.multi-select__skeleton {
  list-style: none;
  display: flex;
  align-items: center;
  padding: var(--s-1) var(--s-2);
  animation: multi-select-fade-in var(--md-sys-motion-duration-short4)
    var(--md-sys-motion-easing-standard) both;
}

@keyframes multi-select-fade-in {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}
.multi-select__skeleton-bar {
  width: 100%;
  height: var(--s-3);
  border-radius: var(--md-sys-shape-corner-small);
  background: color-mix(
    in oklab,
    var(--md-sys-color-inverse-on-surface) 12%,
    transparent
  );
  animation: multi-select-skeleton-pulse
    var(--md-sys-motion-duration-extra-long2)
    var(--md-sys-motion-easing-standard) infinite alternate;
}

@keyframes multi-select-skeleton-pulse {
  from {
    opacity: 1;
  }
  to {
    opacity: 0.45;
  }
}

@media (prefers-reduced-motion: reduce) {
  .multi-select__skeleton,
  .multi-select__skeleton-bar {
    animation: none;
  }
  .multi-select__option,
  .multi-select__group-label,
  .multi-select__group-separator,
  .multi-select__empty {
    transition: none;
  }
}

/* ---------- Empty (no search matches) ---------- */
.multi-select__empty {
  list-style: none;
  padding: var(--s-2) var(--s-2);
  color: var(--xm-color-inverse-on-surface-muted);
  font:
    var(--md-sys-typescale-body-medium-weight)
    var(--md-sys-typescale-body-medium-size) /
    var(--md-sys-typescale-body-medium-line-height)
    var(--md-sys-typescale-body-medium-font);
}