canvas {
  border: 1.5px solid grey;
  width: 100%;
  max-width: 900px;
}
body > div {
  display: flex;
  flex-direction: column;
  align-items: center;
}

body {
  font-family: sans-serif;
}

.controls {
  display: flex;
  flex-direction: row;
  justify-content: center;
}
.controls > * {
  margin: 10px 20px;
}