:root {
  --bg: #0f1115;
  --fg: #e8eaf0;
  --muted: #9aa0ad;
  --panel: #171a21;
  --border: #262a33;
  --accent: #7cc4ff;
  font-family:
    system-ui,
    -apple-system,
    Segoe UI,
    Roboto,
    sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.5;
  padding: 2rem 1.5rem 4rem;
}

header {
  max-width: 900px;
  margin: 0 auto 2rem;
}

h1 {
  margin: 0 0 0.25rem;
  font-size: 1.6rem;
  letter-spacing: -0.01em;
}

h1 .mark {
  color: var(--accent);
}

p.lede {
  color: var(--muted);
  margin: 0;
  max-width: 60ch;
}

main {
  max-width: 900px;
  margin: 0 auto;
  display: grid;
  gap: 1.5rem;
}

.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 1.5rem;
  align-items: flex-end;
  padding: 1rem 1.25rem;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
}

.control {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.control label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--muted);
}

.control input[type='range'] {
  width: 180px;
}

.control output {
  font-variant-numeric: tabular-nums;
  font-size: 0.85rem;
}

.panel {
  padding: 1.25rem;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
}

.panel h2 {
  margin: 0 0 0.75rem;
  font-size: 1rem;
}

.panel h2 .tag {
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--muted);
  margin-left: 0.5rem;
}

.swatches {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.swatch {
  flex: 1 1 60px;
  min-width: 60px;
  height: 88px;
  border-radius: 8px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  display: flex;
  align-items: flex-end;
  justify-content: center;
  padding-bottom: 6px;
  font-size: 0.7rem;
  font-variant-numeric: tabular-nums;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.5);
  color: #fff;
}

.metrics {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 0.75rem;
  margin-top: 1rem;
}

.metric {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.6rem 0.75rem;
}

.metric .k {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--muted);
}

.metric .v {
  font-size: 1.15rem;
  font-variant-numeric: tabular-nums;
  margin-top: 0.15rem;
}

.metric.bad .v {
  color: #ff8b8b;
}

.metric.good .v {
  color: #8bffb0;
}

pre.err {
  color: #ff8b8b;
  white-space: pre-wrap;
}

footer {
  max-width: 900px;
  margin: 2rem auto 0;
  color: var(--muted);
  font-size: 0.8rem;
}

code {
  background: var(--bg);
  padding: 0.1em 0.35em;
  border-radius: 4px;
  border: 1px solid var(--border);
}