#container {
  background-color: skyblue;
  margin: 0px auto;
  padding: 0px;
  width: 400px;
  height: 400px;
}
.square, .circle {
    width: 100px;
    height: 100px;
    display: inline-block;
    float: left;
}
.circle {
    border-radius: 50%;
}
#blockRed {
    background-color: blanchedalmond;
}
#blockYellow {
    background-color: azure;
}
#blockWood {
    background-image: url.('https://images.pexels.com/photos/172276/pexels-photo-172276.jpeg');
}
.square, .circle {
    width: 80px;
    height: 80px;
    display: inline-block;
    float: right   ;
    }