JSFiddle - React, Tailwind, and code Playground

HTML

<img src="http://lorempixel.com/400/200" />
<div class="box-transparent">
    This is some demo Text
</div>

CSS

.box-transparent {
    position: fixed;
    top: 20px;
    left: 20px;
    background-color: rgba(100, 100, 100, 0.6);
    padding: 20px;
}