JSFiddle - React, Tailwind, and code Playground

HTML

<div class="wrapper">
    <div class="img"></div>
</div>

CSS

.img {
    height:200px;
    width:200px;
    margin-left:200px;
    background:green;
}
.img:after {
    height:200px;
    float:left;
    width:200px;
    margin-left:-200px;
    background:silver;
    display:none;
    content:"";
}
.wrapper:hover .img:after{display:block;}