JSFiddle - React, Tailwind, and code Playground
HTML
<div class="left-col">
<div id="div1">
</div>
<div id="div3">
</div>
</div>
<div class="right-col">
<div id="div2">
</div>
<div id="div4">
</div>
</div>CSS
.left-col > *, .right-col > * { border: 1px solid black; margin: 10px; }
.left-col { width: 40%; float:left;}
.right-col { width: 60%; float:right;}
#div1 { height: 200px;}
#div2 { height: 150px;}
#div3 { height: 100px;}
#div4 { height: 150px;}