JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
    <div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
    <div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
<div>
    <img src="//placehold.it/50x50">
</div>
    </div>

CSS

div {
    float:left;
    margin:0 15px 0 0;
}

JavaScript

$("#container div:last-child").css('border', '1px solid red');