/* Full-viewport black stage */
html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  background: #000;
  overflow: hidden;
  font-family: sans-serif;
}

/* Canvas spans the entire viewport */
#canvas {
  position: fixed;
  top: 0;
  left: 0;
  display: block;
  margin: 0;
  padding: 0;
  background: #000;
  touch-action: none;
}

/* Hidden native colour input; triggered programmatically */
#color-picker {
  position: fixed;
  width: 2px;
  height: 2px;
  opacity: 0;
  pointer-events: none;
  left: 0;
  top: 0;
  z-index: 10; /* ensure above canvas when temporarily enabled */
  border: none;
  padding: 0;
  margin: 0;
}

#color-handle {
  position: fixed;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 2px solid #000;
  box-sizing: border-box;
  background: #fff;
  cursor: pointer;
  z-index: 15;
  touch-action: none;
  user-select: none;
}

/* Buy Me a Coffee prompt */
#coffee-card {
  position: fixed;
  right: 16px;
  bottom: 16px;
  max-width: 320px;
  padding: 12px 14px;
  background: rgba(0, 0, 0, 0.85);
  color: #f5f5f5;
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 8px;
  font-size: 14px;
  line-height: 1.4;
  display: none;
  gap: 8px;
  z-index: 20;
}

#coffee-card.visible {
  display: flex;
  flex-direction: column;
}

#coffee-card p {
  margin: 0 0 8px 0;
}

#coffee-button {
  align-self: flex-start;
  padding: 8px 12px;
  background: #0f75ff;
  color: #fff;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  font-size: 14px;
}

#coffee-button:hover,
#coffee-button:focus {
  background: #2f87ff;
}

#coffee-close {
  position: absolute;
  top: 6px;
  right: 8px;
  background: none;
  border: none;
  color: #f5f5f5;
  font-size: 16px;
  cursor: pointer;
  line-height: 1;
  padding: 4px;
}