html, body {
  margin: 0;
  padding: 0;
}
canvas {
  display: block;
}

.controls {
  position: fixed;
  top: 20px;
  left: 20px;
  background: #fff;
  padding: 20px;
  box-sizing: border-box;
  display: flex;
  flex-direction: column;
  opacity: 0.5;
  border-radius: 5px;
}

.controls:hover {
  opacity: 1;
}

.imgInput {
  margin-bottom: 20px;
}

.imgSave {
  margin-top: 20px;
}