html{
  height:100%;
}

body{
  height:100%;
  margin: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}

#canvas{
  width: 65vmin;
  height: 80vmin;
  background-color: rgb(81,103,179);
  position: relative;
}

#secondring{
  background-color: rgb(92,141,73);
  position: absolute;
  left: vmin;
  top: 20vmin;
  width: 43vmin;
  height: 60vmin;
}

#thirdring{
  background-color: rgb(178,91,66);
  position: absolute;
  left: vmin;
  top: 50vmin;
  width: 25vmin;
  height: 30vmin;
}