JSFiddle - React, Tailwind, and code Playground

HTML

<div class="div1">
   <div class="div2">
      <div class="div3">
         <!-- I need div3 with full width and full height -->
      </div>
   </div>
</div>

CSS

.div1 {
  position: relative;
  width: 350px;
  height: 350px;
  background-color: blue;
}

.div2 {
  position: absolute;
  width: 250px;
  height: 250px;
  background-color: red;
  left: 50px;
  top: 50px;
}

.div3 {
  position: absolute;
  background-color: green;
  left: 0px;
  top: 0px;
  right: 0px;
  bottom: 0px;
}