JSFiddle - React, Tailwind, and code Playground

HTML

<div class="main">
    <div class="one">1</div>
    <div class="two">2</div>
</div>

CSS

.main {
    width:500px;
    background:#F00;
    overflow:hidden;
}

.one {
    float:left;
    width:70%;
    height:200px;
    background:#0F0;
}

.two {
    float:left;
    width:20%;
    height:200px;
    background:#00F;
}