JSFiddle - React, Tailwind, and code Playground

HTML

<img class="click-to-top" style="top:10px;left:10px">1</div>
<img class="click-to-top" style="top:20px;left:90px">2</div>
<img class="click-to-top" style="top:60px;left:70px">3</div>
<img class="click-to-top" style="top:90px;left:30px">4</div>

CSS

div.click-to-top {
    position: absolute;
    background-color: rgba(255, 200, 200, 0.7);
    border: black solid 1px;
    width: 100px;
    height: 100px;
}

JavaScript

// Answer for http://stackoverflow.com/a/13112731/592125

$('img').click(function(){
    var topZ = 0;
    $('img').each(function(){
        var thisZ = parseInt($(this).css('z-index'), 10);
        if (thisZ > topZ){
            topZ = thisZ;
        }
    });
    $(this).css('z-index', topZ+1);
});