html,
body {
  margin: 0;
  padding: 0;
}

canvas {
  padding-left: 0;
  padding-right: 0;
  padding-top: 0;
  padding-bottom: 0;
  margin-left: auto;
  margin-right: auto;
  margin-top: 50px;
  margin-bottom: auto;
  display: block;
  width: 800px;
}

.parent {
  display: grid;
  grid-template-columns: auto auto auto;
}

.child {
  padding: 5px;
  box-sizing: border-box;
}

.child img {
  width: 200px;
  height: auto;
}