body {
  font-family: sans-serif;
  max-width: 900px;
  margin: 2rem auto;
}

.crop-frame {
  display: inline-block;
  padding: 12px;
  border: 2px solid #aaa;
  background: #f8f8f8;
  margin-bottom: 1rem;
}

canvas {
  display: block;
  width: 600px;
  height: auto;
  touch-action: none; /* required for pointer events */
}

button {
  margin: 0.5rem 0.5rem 0.5rem 0;
}