html, body {
  margin: 0;
  padding: 0;
  overflow: hidden;
}
canvas {
  display: block;
}
button {
  font-size: 0.9rem;
  padding: 6px 8px;
  border-radius: 8px;
  border: 1px solid rgba(0,0,0,0.25);

  background:
    linear-gradient(
      180deg,
      #ffffff,
      #dbe9f9
    );

  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.8),
    0 2px 4px rgba(0,0,0,0.25);
}
select {
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;

  font-size: 0.9rem;
  padding: 6px 8px;
  border-radius: 8px;
  border: 1px solid rgba(0,0,0,0.25);
  background: linear-gradient(180deg, #ffffff, #dbe9f9);
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.8), 0 2px 4px rgba(0,0,0,0.25);
  cursor: pointer;
}

/* optional: add a custom arrow */
select::after {
  content: "▼";
  position: absolute;
  right: 10px;
  pointer-events: none;
}

button:hover {
  background:
    linear-gradient(
      180deg,
      #ffffff,
      #cfe2ff
    );
}
.panel {
  pointer-events: auto;
  padding: 14px;
  min-width: 240px;

  background:
    linear-gradient(
      180deg,
      rgba(255,255,255,0.9),
      rgba(210,230,255,0.85)
    );

  border-radius: 14px;
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.9),
    0 12px 30px rgba(0,0,0,0.25);

  backdrop-filter: blur(6px);

  display: flex;
  flex-direction: column;
  gap: 10px;
}
button:active {
  box-shadow:
    inset 0 2px 6px rgba(0,0,0,0.25);
}
.checkbox {
  font-size: 0.85rem;
  display: flex;
  align-items: center;
  gap: 6px;
}