JSFiddle - React, Tailwind, and code Playground

HTML

<div class='container'>
    <div class='ad'>One</div>
    <div class='ad'>One</div>
    <div class='ad'>One</div>
    <div class='ad'>One</div>
</div>

CSS

.container {
    width:660px;
    margin:0 auto;
    text-align:center;
}
.ad {
    width:140px;
    height:140px;
    display:inline-block;
    background:#00A3E8;
}