/* ActivityHeatmap — day × time grid of rounded cells (owner-approved adoption
   of the reference "Activity by time" widget, 2026-07-07). Cells wear the
   bright brand-cyan sequential ramp by intensity (never past cyan-600); the
   scale legend names the ramp ends; every cell carries a hover/focus
   read-out. Labels wear text tokens. Visual source: tokens.css. */

.heatmap {
  box-sizing: border-box;
  display: flex;
  flex-direction: column;
  gap: 16px;
  width: 100%;
  max-width: 640px;
  padding: 21px;
  background: var(--canvas);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-1);
  font-family: var(--font-sans);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
}

.heatmap__head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
}
.heatmap__title {
  margin: 0;
  font-size: var(--fs-6);
  font-weight: var(--fw-heavy);
  letter-spacing: -0.01em;
}
.heatmap__sub {
  margin: 2px 0 0;
  font-size: var(--fs-2);
  color: var(--text-4);
}

/* Grid: time labels left, day labels top, 7×6 rounded cells. */
.heatmap__plot {
  position: relative;
  display: grid;
  grid-template-columns: 44px repeat(7, 1fr);
  gap: 5px;
  align-items: center;
}
.heatmap__day,
.heatmap__time {
  font-size: var(--fs-1);
  color: var(--text-4);
  text-align: center;
}
.heatmap__time {
  text-align: right;
  padding-right: 8px;
  font-variant-numeric: tabular-nums;
}

.heatmap__cell {
  height: 28px;
  border: 0;
  border-radius: var(--r-sm);
  padding: 0;
  cursor: pointer;
  transition: filter var(--dur-2) var(--ease-out);
}
.heatmap__cell:hover {
  filter: brightness(0.95) saturate(1.2);
}
.heatmap__cell:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}
.heatmap__cell--l1 {
  background: var(--cyan-50);
}
.heatmap__cell--l2 {
  background: var(--chart-seq-100);
}
.heatmap__cell--l3 {
  background: var(--chart-seq-200);
}
.heatmap__cell--l4 {
  background: var(--chart-seq-300);
}
.heatmap__cell--l5 {
  background: var(--chart-seq-400);
}
.heatmap__cell--l6 {
  background: var(--chart-seq-600);
}

/* Scale legend — Less → More. */
.heatmap__scale {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 5px;
  font-size: var(--fs-1);
  color: var(--text-4);
}
.heatmap__scale-swatch {
  width: 16px;
  height: 10px;
  border-radius: 4px;
}
.heatmap__scale span {
  margin: 0 3px;
}
/* Real range of the ramp — the scale must be readable without hover. */
.heatmap__scale-range {
  margin-left: 10px;
  color: var(--text-4);
  font-variant-numeric: tabular-nums;
}

/* Shared hover readout (value leads, label follows). */
.chart-tip {
  position: absolute;
  pointer-events: none;
  transform: translate(-50%, calc(-100% - 10px));
  display: none;
  flex-direction: column;
  gap: 1px;
  padding: 7px 10px;
  border-radius: var(--r-md);
  background: var(--ink-900);
  color: #fff;
  font-size: var(--fs-2);
  line-height: 1.35;
  white-space: nowrap;
  box-shadow: var(--shadow-2);
  z-index: 2;
}
.chart-tip.is-visible {
  display: flex;
}
.chart-tip__value {
  font-weight: var(--fw-heavy);
  font-size: var(--fs-3);
  font-variant-numeric: tabular-nums;
}
.chart-tip__label {
  color: rgba(255, 255, 255, 0.72);
}