JSFiddle - React, Tailwind, and code Playground

HTML

<div>
    <aside></aside>
    <section></section>
    <section></section>
</div>

<div>
    <section></section>
    <section></section>
    <aside></aside>
</div>

CSS

html, body {margin:0;padding:0;}
div {
    display:table; 
    width:90%;
    min-height:200px;
    margin:0 auto;
}
section, aside {
    display:table-cell;
    height:100%;
    border:1px solid;
}
aside {
    width:300px;
}