body {
  margin: 0;
}

.relative {
  position: relative;
  top: 20px;
  left: 20px;
}

.absolute {
  position: absolute;
  top: 20px;
  left: 20px;
}

.parent {
  margin-top: 50px;
  margin-left: 50px;
  width: 200px;
  height: 200px;
  background-color: red;
}

.child {
  width: 100px;
  height: 100px;
  background-color: lime;
}