* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  color: #222;
  background: #fff;
  overflow: hidden;
}

#stage {
  position: fixed;
  inset: 0;
  width: 100vw;
  height: 100vh;
  display: block;
  cursor: grab;
  background: #fff;
  touch-action: none;
}

#stage:active {
  cursor: grabbing;
}

#panel {
  position: fixed;
  top: 16px;
  left: 16px;
  width: 280px;
  background: rgba(255, 255, 255, 0.94);
  border: 1px solid #ccc;
  border-radius: 8px;
  padding: 14px 16px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
  backdrop-filter: blur(6px);
  font-size: 0.88rem;
  z-index: 10;
  user-select: none;
}

#panel h1 {
  margin: 0 0 10px;
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: 0.01em;
}

.row {
  margin-bottom: 10px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.row label {
  font-weight: 500;
  color: #444;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.row label.inline {
  flex-direction: row;
  gap: 8px;
  justify-content: flex-start;
}

.row label.inline input[type="checkbox"] {
  margin: 0;
}

.row.toggles {
  flex-direction: row;
  gap: 14px;
  flex-wrap: wrap;
}

.row-controls {
  display: flex;
  gap: 6px;
}

.row-controls select {
  flex: 1;
  min-width: 0;
}

#panel select,
#panel input[type="range"],
#panel button {
  font: inherit;
  padding: 4px 8px;
  border: 1px solid #bbb;
  border-radius: 4px;
  background: #fff;
  cursor: pointer;
}

#panel input[type="range"] {
  padding: 0;
  width: 100%;
}

#panel button:hover {
  background: #f0f0f0;
}

#panel button#random {
  padding: 2px 8px;
  font-size: 1rem;
  line-height: 1;
}

.row.buttons {
  flex-direction: row;
  gap: 6px;
}

.row.buttons button {
  flex: 1;
}

#angle-readout,
#zoom-readout {
  font-variant-numeric: tabular-nums;
  color: #888;
  font-weight: 400;
}

.hint {
  margin: 8px 0 0;
  font-size: 0.75rem;
  color: #888;
}

details.palette {
  margin: 4px 0 10px;
  border: 1px solid #ddd;
  border-radius: 5px;
  padding: 6px 10px;
  background: rgba(255, 255, 255, 0.6);
}

details.palette > summary {
  cursor: pointer;
  font-weight: 500;
  color: #444;
  list-style: none;
  user-select: none;
}

details.palette > summary::-webkit-details-marker {
  display: none;
}

details.palette > summary::before {
  content: "▶ ";
  font-size: 0.7rem;
  color: #999;
}

details.palette[open] > summary::before {
  content: "▼ ";
}

.palette-section {
  margin-top: 6px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.palette-title {
  font-size: 0.78rem;
  color: #666;
  font-weight: 500;
}

.swatch-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
}

label.swatch {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 0.78rem;
  color: #555;
  cursor: pointer;
  font-weight: 400;
}

label.swatch input[type="color"] {
  width: 28px;
  height: 22px;
  border: 1px solid #bbb;
  border-radius: 3px;
  padding: 0;
  background: #fff;
  cursor: pointer;
}