.lab-timeline {
  /* N columns = number of entries */
  --gap-x: 24px;
  --track-h: 32px;
  --lane-pad: 0px; /* no side padding per request */
  --col-min: 180px; /* ensure readable minimum width per entry */
  display: grid;
  grid-template-columns: repeat(var(--lab-timeline-count, 1), minmax(var(--col-min), 1fr));
  grid-template-rows: auto var(--track-h) auto;
  column-gap: var(--gap-x);
  row-gap: 26px; /* extra space so pointers don't overlap text */
  align-items: center;
  position: relative;
  width: 100%;
  padding-inline: var(--lane-pad);
  /* Mobile friendliness: allow horizontal scroll when needed */
  overflow-x: auto;
  overflow-y: visible;
  -webkit-overflow-scrolling: touch;
  scroll-snap-type: x proximity;
}

/* The lane is the track background and a grid container for caps */
.lab-timeline__lane {
  grid-column: 1 / -1;
  grid-row: 2;
  display: grid;
  grid-template-columns: repeat(var(--lab-timeline-count, 1), minmax(var(--col-min), 1fr));
  column-gap: var(--gap-x);
  height: var(--track-h);
  background: var(--color-neutral-medium);
  border-radius: calc(var(--track-h) / 2);
  position: relative;
  /* don't clip pointers; keep ends clean via cap inset */
}

.lab-timeline__cell {
  display: flex;
  align-items: center;
  scroll-snap-align: center;
}

/* Blue/grey segment that sits on top of the track for each item */
.lab-timeline__cap {
  grid-row: 2;
  height: calc(var(--track-h) * 0.9);
  --cap-inset: 10px; /* leave slight grey at both ends */
  width: calc(100% - (var(--cap-inset) * 2));
  margin-inline: var(--cap-inset);
  background: var(--color-brand-tertiary);
  border-radius: 6px;
  position: relative;
  z-index: 2; /* ensure above lane */
}

/* Directional pointers (alternating) */
.lab-timeline__cap--top::before { /* points up */
  content: '';
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  bottom: 100%;
  width: 0; height: 0;
  border-left: 10px solid transparent;
  border-right: 10px solid transparent;
  border-bottom: 16px solid var(--color-brand-tertiary);
  z-index: 2;
}

.lab-timeline__cap--bottom::after { /* points down */
  content: '';
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  top: 100%;
  width: 0; height: 0;
  border-left: 10px solid transparent;
  border-right: 10px solid transparent;
  border-top: 16px solid var(--color-brand-tertiary);
  z-index: 2;
}

/* Alternate item coloring: blue (default) and grey */
.lab-timeline__cap.is-grey { background: var(--color-neutral-medium); }
.lab-timeline__cap.is-grey.lab-timeline__cap--top::before { border-bottom-color: var(--color-neutral-medium); }
.lab-timeline__cap.is-grey.lab-timeline__cap--bottom::after { border-top-color: var(--color-neutral-medium); }

.lab-timeline__meta {
  text-align: center;
  position: relative;
  z-index: 3; /* keep text above pointers if they overlap visually */
  scroll-snap-align: center;
}
.lab-timeline__meta--top { grid-row: 1; }
.lab-timeline__meta--bottom { grid-row: 3; }

.lab-timeline__meta--top { padding-bottom: 6px; }
.lab-timeline__meta--bottom { padding-top: 6px; }

.lab-timeline__year {
  font-family: 'Roboto', system-ui, -apple-system, Segoe UI, Helvetica, Arial, sans-serif;
  font-weight: 700;           /* Roboto 700 */
  font-size: 24px;            /* per request */
  line-height: 1.2;
}

/* Year color matches the segment color every other */
.lab-timeline__meta.is-blue .lab-timeline__year { color: var(--color-brand-tertiary); }
.lab-timeline__meta.is-grey .lab-timeline__year { color: var(--color-neutral-medium); }

.lab-timeline__desc {
  margin-top: 6px;
  font-family: 'Roboto', system-ui, -apple-system, Segoe UI, Helvetica, Arial, sans-serif;
  font-weight: 400;          /* Roboto 400 */
  font-size: 14px;           /* per request */
  color: rgba(255, 255, 255, 0.8);
}

@media (max-width: 768px) {
  .lab-timeline {
    --gap-x: 16px;
    --track-h: 26px;
    --col-min: 220px; /* keep items legible on tablets */
  }
  .lab-timeline__cap { --cap-inset: 8px; }
  .lab-timeline__year { font-size: 1.1rem; }
  .lab-timeline__desc { font-size: 13px; }
  .lab-timeline__cap--top::before {
    border-left-width: 9px;
    border-right-width: 9px;
    border-bottom-width: 14px;
  }
  .lab-timeline__cap--bottom::after {
    border-left-width: 9px;
    border-right-width: 9px;
    border-top-width: 14px;
  }
}

@media (max-width: 480px) {
  .lab-timeline {
    --gap-x: 12px;
    --track-h: 22px;
    --col-min: 180px; /* allow comfortable single-card view */
  }
  .lab-timeline__cap { --cap-inset: 6px; }
  .lab-timeline__year { font-size: 1rem; }
  .lab-timeline__desc { font-size: 12px; }
  .lab-timeline__cap--top::before {
    border-left-width: 8px;
    border-right-width: 8px;
    border-bottom-width: 12px;
  }
  .lab-timeline__cap--bottom::after {
    border-left-width: 8px;
    border-right-width: 8px;
    border-top-width: 12px;
  }
}