JSFiddle - React, Tailwind, and code Playground

HTML

<img class="fixed-background" src="http://s3.amazonaws.com/rapgenius/cats-animals-kittens-background.jpg"/>

CSS

.fixed-background {
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    width: 100%;
    overflow: hidden;
}

img {
    height: auto;
    width: auto;
    min-width: 100%;
    min-height: 100%;
}