JSFiddle - React, Tailwind, and code Playground

HTML

<div class="splash-image-wrap splash-image">
    <img class="splash-image-bg" src="https://upload.wikimedia.org/wikipedia/commons/1/1e/Large_Siamese_cat_tosses_a_mouse.jpg" alt="image-bg">
</div>

JavaScript

function updatePageForTopImg() {
        // background image using size cover
        // top background image
        $('.splash-image-wrap')
            .css('background-image', 'url(' + $(".splash-image-bg").attr("src") + ')')
            .css('background-size', 'cover')
            .css('background-position', 'center');
    }

$(function () {
    updatePageForTopImg();
});