h1{
  text-align: center;
}
#canvas{
  position: relative;
  width: 81vmin;
  height: 81vmin;
  background-color: #556;
  margin: auto
}

#col2{
  left: 27vmin;
  position: absolute;
  background-color: rgb(144,50,40);
  width: 27vmin;
  height: 81vmin;
}

#col3{
  left: 54vmin;
  position: absolute;
  background-color: goldenrod;
  width: 27vmin;
  height: 81vmin;
}