JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/bulma/0.3.0/css/bulma.css">
<HTML>
<body>
<div class="columns reverse-row-order">
    <div class="column bar">Bar</div>  
    <div class="column foo">Foo</div>
</div>
</body>
</HTML>

CSS

body, html {
    background-color: blue;
}


@media only screen and (min-width: 769px) {
    body, html {
        background-color: red;
    }

   .reverse-row-order{
     flex-direction:row-reverse;
   }
}