#wrapper{
  width: 900px;
  background: #D0D0D0;
  position: relative;
}
#element3{
  
  top: 0px;
  left: 0px;
}
.element{
  display: flex;
  justify-content: center;
  align-items: center;
  width: 200px;
  height: 200px;
  background: #D00000;
  border: solid;
  border-color: #000000;
  border-with: 3px;
  font-size: 2rem;
}.sub-element{
  position: absolute;

  display: flex;
  justify-content: center;
  align-items: center;
  width: 50px;
  height: 50px;
  background: #D00000;
  border: solid;
  border-color: #000000;
  border-with: 2px;
}