JSFiddle - React, Tailwind, and code Playground

HTML

<div data-content="Here is a caption" class="image">
    <img src="http://www.newyorker.com/online/blogs/photobooth/NASAEarth-01.jpg" alt="" />
</div>

CSS

.image {
    position:relative;
    height: 200px;
    width:200px
        
}
.image img {
    width:100%;
    vertical-align:top;
}
.image:after, .image:before {
    position:absolute;
    opacity:0;
    transition: all 0.5s;
    -webkit-transition: all 0.5s;
}
.image:after {
    content:'\A';
    width:100%; height:100%;
    top:0; left:0;
    background:rgba(0,0,0,0.6);
}
.image:before {
    content: attr(data-content);
    width:100%;
    color:#fff;
    z-index:1;
    vertical-align:center;
    /*bottom:0;*/
    padding:30px 30px;
    top:30%;
    text-align:center;
    background:red;
    box-sizing:border-box;
    -moz-box-sizing:border-box;
    vertical-align: middle;
}
.image:hover:after, .image:hover:before {
    opacity:1;
}