<div class="relative">W3TR
 <div class="absolute">W3TR</div>
</div>

div {
  border: 3px solid red;
}
.relative  {
  width: 300px;
  height: 300px;
  position: relative;
}
.absolute  {
  position: absolute;
  width: 150px;
  height: 150px;
  left: 50%;
  top: 50%;
  margin-left: -75px;
  margin-top:-75px;
}