JSFiddle - React, Tailwind, and code Playground

HTML

<div class="contain">
<div class="featuredcontainer"></div>
<div class="navcontainer"></div>
</div>

CSS

.contain {
    position:relative;
    width:50%;
    height:100%;
    margin:30px auto;
}
.featuredcontainer, .navcontainer {
    float:left;
    width:45%;
    height:10px;
    background:#00cc33;
    border:1px solid black;
}