/*
 * FILMSTRIP
 * =========
 * One scrollable rail of columns. Each column is a single timestamp,
 * with HAR1 on top, HAR2 below, the shared timestamp underneath. The
 * two padded frame arrays come in the same length and grid step, so
 * the eye reads each column as a single timeslice and the divergence
 * between the two HARs is obvious side-by-side.
 *
 * Columns where the two HARs disagree on visual progress get a
 * coloured accent (mild amber for small gaps, strong red for large
 * gaps) so the regression announces itself before you have to look
 * at the pixels.
 */

.filmstrip {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: 12px;
}

.filmstrip-legend {
  display: flex;
  gap: 16px;
  padding: 0 4px;
  font-size: 0.85rem;
  color: var(--color-text-secondary);
}

.filmstrip-legend-label {
  display: inline-flex;
  align-items: center;
  gap: 6px;

  &::before {
    content: '';
    width: 10px;
    height: 10px;
    border-radius: 2px;
    background: var(--color-border);
  }
}
.filmstrip-legend-label--har1::before { background: var(--color-blue); }
.filmstrip-legend-label--har2::before { background: #f97316; /* orange — deliberately
  distinct from HAR1 blue so the eye can tell which row is which without
  reading the label. */ }

.filmstrip-rail {
  display: flex;
  gap: 10px;
  padding: 8px;
  overflow-x: auto;
  scroll-snap-type: x proximity;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  user-select: none;

  /* While the user drags the rail to scroll horizontally, swap the
     cursor and silence the column hover affordances so it feels like
     a panning interaction not a series of micro-clicks. */
  &.is-dragging {
    cursor: grabbing;

    .filmstrip-column {
      pointer-events: none;
    }
  }
}
.filmstrip-rail:focus-visible {
  outline: 2px solid var(--color-blue);
  outline-offset: 2px;
}

.filmstrip-column {
  flex: 0 0 auto;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 4px;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  background: var(--color-surface-card);
  scroll-snap-align: start;
  transition: border-color var(--motion-fast), background var(--motion-fast);
}

.filmstrip-column:hover {
  border-color: var(--color-info-border);
}

/* Divergence accent — column shows the two HARs as visually different
   at this timestamp. Mild amber, strong red. The colours only paint
   the border + caption so the screenshot content stays uncoloured. */
.filmstrip-column--diff-mild {
  border-color: var(--color-warning);
  background: var(--color-warning-bg);

  .filmstrip-time {
    color: var(--color-warning);
    font-weight: var(--font-weight-semibold);
  }
}
.filmstrip-column--diff-strong {
  border-color: var(--color-error);
  background: rgba(220, 38, 38, 0.07);

  .filmstrip-time {
    color: var(--color-error);
    font-weight: var(--font-weight-semibold);
  }
}

.filmstrip-cell {
  position: relative;
  display: block;
  padding: 0;
  margin: 0;
  background: var(--color-surface-card);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-sm);
  overflow: hidden;
  cursor: zoom-in;
  transition: border-color var(--motion-fast),
              box-shadow var(--motion-fast),
              transform var(--motion-fast);
}

.filmstrip-cell:hover,
.filmstrip-cell:focus-visible {
  box-shadow: var(--shadow-md);
  transform: translateY(-1px);
}

/*
 * HAR-specific colour treatment — left edge stripe + matching badge
 * so the eye lands on HAR1 vs HAR2 immediately, without having to
 * consult the legend on every column. Picked deliberately
 * dissimilar colours (blue / orange) so colour-blind users still get
 * a high-contrast difference. The badge gives a redundant numeric
 * cue for safety.
 */
.filmstrip-cell--har1 {
  border-left: 4px solid var(--color-blue);
}
.filmstrip-cell--har2 {
  border-left: 4px solid #f97316;
}
.filmstrip-cell--har1:hover,
.filmstrip-cell--har1:focus-visible {
  border-color: var(--color-blue);
  border-left-color: var(--color-blue);
}
.filmstrip-cell--har2:hover,
.filmstrip-cell--har2:focus-visible {
  border-color: #f97316;
}

.filmstrip-cell-badge {
  position: absolute;
  top: 4px;
  left: 4px;
  z-index: 1;
  width: 18px;
  height: 18px;
  border-radius: 999px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 0.7rem;
  font-weight: var(--font-weight-semibold);
  color: white;
  background: rgba(15, 23, 42, 0.6);
  pointer-events: none;
}
.filmstrip-cell--har1 .filmstrip-cell-badge { background: var(--color-blue); }
.filmstrip-cell--har2 .filmstrip-cell-badge { background: #f97316; }

.filmstrip-cell img {
  display: block;
  width: 240px;
  height: auto;
  max-height: 260px;
  object-fit: cover;
}

.filmstrip-cell--missing {
  display: block;
  width: 240px;
  height: 140px;
  background: repeating-linear-gradient(
    45deg,
    var(--color-surface),
    var(--color-surface) 8px,
    var(--color-surface-card) 8px,
    var(--color-surface-card) 16px
  );
  border: 1px dashed var(--color-border);
  border-radius: var(--radius-sm);
}

.filmstrip-time {
  text-align: center;
  font-size: 0.78rem;
  color: var(--color-text-secondary);
  font-variant-numeric: tabular-nums;
  margin-top: 2px;
}

@media (max-width: 640px) {
  .filmstrip-cell img,
  .filmstrip-cell--missing {
    width: 170px;
    max-height: 190px;
  }
}