/* ── Reset & base ─────────────────────────────────────────────────────────── */

/* box-sizing: border-box makes width/height include padding and border,
   which is much more intuitive than the default browser behaviour. */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: system-ui, sans-serif; /* uses the OS default font — no import needed */
  background: #f0f2f5;
  color: #222;
  padding: 1.5rem;
}

header h1 {
  font-size: 1.75rem;
  margin-bottom: 1.5rem;
  color: #1a1a2e;
}


/* ── KPI cards ────────────────────────────────────────────────────────────── */

/* CSS Grid with auto-fit + minmax makes the cards responsive automatically:
   they fill the row and wrap to the next line when the screen is too narrow.
   No media queries needed. */
.kpi-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
  margin-bottom: 2rem;
}

.card {
  background: #ffffff;
  border-radius: 8px;
  padding: 1.25rem 1rem;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.08);
}

.card h2 {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: #888;
  margin-bottom: 0.5rem;
}

.kpi-value {
  font-size: 1.75rem;
  font-weight: 700;
  color: #1a1a2e;
}


/* ── Chart sections ───────────────────────────────────────────────────────── */

.chart-section {
  background: #ffffff;
  border-radius: 8px;
  padding: 1.5rem;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.08);
  margin-bottom: 1.5rem;
}

.chart-section h2 {
  font-size: 1rem;
  color: #555;
  margin-bottom: 1rem;
}

/* Limit chart height so tall charts don't push content off screen */
.chart-section canvas {
  max-height: 320px;
}