JSFiddle - React, Tailwind, and code Playground

HTML

<div class="box">
  <div class="b1"></div>
  <div class="b2"></div>
  <div class="b3"></div>
  <div class="b4"></div>
</div>

CSS

body {margin:0;}
.box {
  width:100%;
  display:flex;
  flex-wrap: wrap;
}
.b1 {
  width:45%;
  height:100px;
  background-color:red;
}
.b2 {
  width:45%;
  height:150px;
  background-color:blue;
}
.b3 {
  width:45%;
  height:120px;
  background-color:green;
}
.b4 {
  width:45%;
  height:90px;
  background-color:coral;
}