body > * 
{ 
  width: 100px;
  height: 100px;
  overflow: auto;
  border: thick solid purple;
  margin: 10px; 
}

body > * > *
{ 
  margin: 10px; 
  border: medium solid green; 
  background: yellow;
  width: 200px; 
  height: 200px;
}