JSFiddle - React, Tailwind, and code Playground

HTML

<div class="main">
  <div class="block1">
    Block 1
  </div>
  <div class="block2">
    Block 2
  </div>

  <div class="popup">
    PopUp Block
  </div>
</div>

CSS

.main {
   
 }

 .block1 {
   height: 200px;
   background: blue;
 }

 .block2 {
   height: 200px;
   background: aqua;
 }

 .block2:hover {}

 .popup {
   height: 150px;
   background: beige;
   width: 94%;
   margin-left: 2%;
   margin-top: 2%;
   /*display: none;*/
 }