JSFiddle - React, Tailwind, and code Playground
HTML
<div class="outer">
<span>Outer</span>
<div class="inner">
<span>Inner</span>
</div>
</div>
CSS
.outer {
width:80%;
height:500px;
background:#eee;
position:relative;
text-align:right;
}
.inner {
position:absolute;
top:0;
bottom:0;
width:50%;
background:#aaa;
}