:root {
  color-scheme: dark;
  --sky: #081026;
  --panel: #101b3a;
  --line: #22325e;
  --text: #dfe9fb;
  --muted: #9fb2d6;
  --accent: #8cc4ff;
  --accent-ink: #061026;
}

* {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--sky);
  color: var(--text);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  padding: max(16px, env(safe-area-inset-top)) max(16px, env(safe-area-inset-right))
    max(16px, env(safe-area-inset-bottom)) max(16px, env(safe-area-inset-left));
}

header,
main,
footer {
  max-width: 1080px;
  margin: 0 auto;
}

h1 {
  font-size: 1.6rem;
  font-weight: 600;
  margin: 0 0 0.25rem;
  letter-spacing: 0.02em;
}

header p {
  margin: 0 0 1rem;
  color: var(--muted);
}

main {
  display: grid;
  gap: 1rem;
}

.stage {
  position: relative;
  width: 100%;
  max-width: 640px;
  aspect-ratio: 1;
  margin: 0 auto;
}

canvas {
  display: block;
  width: 100%;
  height: 100%;
  border-radius: 12px;
  background: var(--sky);
  touch-action: manipulation;
  cursor: pointer;
}

#overlay {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  margin: 0;
  padding: 1rem;
  text-align: center;
  color: var(--muted);
  pointer-events: none;
}

#overlay:empty {
  display: none;
}

.controls {
  display: grid;
  gap: 0.75rem;
  align-content: start;
  min-width: 0;
}

.row {
  display: flex;
  gap: 0.5rem;
}

button,
select,
input[type="number"] {
  font: inherit;
  color: var(--text);
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 10px;
  min-height: 44px;
  touch-action: manipulation;
}

button {
  flex: 1;
  padding: 0 1rem;
  cursor: pointer;
}

button:disabled {
  opacity: 0.5;
  cursor: default;
}

#play {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--accent-ink);
  font-weight: 600;
}

#status {
  margin: 0;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}

.field {
  display: grid;
  gap: 0.25rem;
  color: var(--muted);
}

select {
  width: 100%;
  padding: 0 0.75rem;
}

.note {
  margin: 0;
  color: var(--muted);
  font-size: 0.9rem;
}

details {
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 0 0.75rem;
}

summary {
  min-height: 44px;
  display: flex;
  align-items: center;
  cursor: pointer;
}

details[open] {
  padding-bottom: 0.75rem;
}

.slider {
  display: grid;
  grid-template-columns: 1fr 6.5rem;
  grid-template-areas: "label value" "range range";
  gap: 0.25rem 0.5rem;
  align-items: center;
  margin-top: 0.75rem;
}

.slider label {
  grid-area: label;
}

.slider label small {
  color: var(--muted);
}

.slider input[type="number"] {
  grid-area: value;
  width: 100%;
  padding: 0 0.5rem;
  text-align: right;
  font-variant-numeric: tabular-nums;
}

.slider input[type="range"] {
  grid-area: range;
  width: 100%;
  height: 32px;
  accent-color: var(--accent);
}

footer {
  margin-top: 1.5rem;
  color: var(--muted);
  font-size: 0.9rem;
}

a {
  color: var(--accent);
}

@media (min-width: 900px) {
  main {
    grid-template-columns: minmax(0, 640px) minmax(280px, 1fr);
    align-items: start;
  }

  .stage {
    margin: 0;
  }
}