JSFiddle - React, Tailwind, and code Playground

HTML

<header>
<div id="title">
<img src="http://worldwide.blackberry.com/assets_emea/local/uk/images/homepage/homepage_playbookOS2_uk.jpg" alt="" />
</div>
    <ul id="prenex">
        <li><a href="#">&lt; Prev</a></li>
            <li><a href="#">Next &gt;</a></li>
    </ul>
</header>

JavaScript

var imageResizer = function(){
    var img = $('#title img').width();
    var div = $('#title').width();
    
    console.log(img);
    
    if(img > div){
        $('#title img').addClass('tall');
        }else{
        $('#title img').addClass('wide');
        }
};

$('a').click(function(){
    alert('hello'); imageResizer()
        });