.outer {
  width: 510px;
  height: 210px;
  background-color: lightgrey;
  position: relative;
}

.box1 {
  &::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 500px;
    height: 200px;
    background-color: pink;
    box-sizing: border-box;
    transform: scale(0.6);
  }
  position: absolute;
  top: 0;
  left: 0;
  width: 500px;
  height: 200px;
  box-sizing: border-box;
  border: 1px dashed black;
}

.box2 {
  &::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 470px;
    height: 170px;
    background-color: lightgreen;
    border: 1px solid green;
    box-sizing: border-box;
    transform: scale(0.6);
  }
  position: absolute;
  top: 30px;
  left: 30px;
  width: 470px;
  height: 170px;
  border: 1px dashed black;
  box-sizing: border-box;
}