JSFiddle - React, Tailwind, and code Playground

HTML

<div class="images">
    <img src="http://placehold.it/100x100" class="one" />
    <img src="http://placehold.it/100x100/000000" class="two" />
</div>

CSS

.two {
    opacity: .75;
    position: relative;
    top: 50px; left: -50px;
    transition: opacity 2s;
}

.toggled .two {
    opacity: .1;
}

JavaScript

(function () {

    document.querySelector( ".images" ).addEventListener( "click", function () {
        this.classList.toggle( "toggled" );
    });
    
}());