body {
  background-color: lightblue;
}
#main {
  display:flex;
  justify-content: center;
}
#canvas {
  outline:3px groove brown;
  background-color: ivory;
  margin:2vmin;
}
#buttons {
  display:flex;
  flex-direction: column;
  justify-content: space-around;
  align-items: center;
  margin-top:2vmin;
}
#buttons div {
  cursor: pointer;
  font-size: 3vmin;
  font-family: sans-serif;
  padding:1vmin 2vmin;
  background-color: beige;
  border:.5vmin solid brown;
  border-radius: 20%;
}
@media (orientation:portrait) {
  #main {
    flex-direction: column;
    align-items: center;
  }
  #buttons {
    flex-direction:row; flex-wrap:wrap;
  }
  #buttons div {margin: 1vmin;}
}