JSFiddle - React, Tailwind, and code Playground

HTML

<div id="main">
    <img src="http://www.sibuya.co.kr/design/sibuya/2013new/roll/lolco_1.jpg" />
</div>

<div id="gallery">
    <img src="http://www.sibuya.co.kr/design/sibuya/2013new/roll/lolco_total_1.jpg" data-img="http://www.sibuya.co.kr/design/sibuya/2013new/roll/lolco_1.jpg" />
    <img src="http://www.sibuya.co.kr/design/sibuya/2013new/roll/lolco_total_2.jpg" data-img="http://www.sibuya.co.kr/design/sibuya/2013new/roll/lolco_2.jpg" />
    <img src="http://www.sibuya.co.kr/design/sibuya/2013new/roll/lolco_total_3.jpg" data-img="http://www.sibuya.co.kr/design/sibuya/2013new/roll/lolco_3.jpg" />
    <img src="http://www.sibuya.co.kr/design/sibuya/2013new/roll/lolco_total_4.jpg" data-img="http://www.sibuya.co.kr/design/sibuya/2013new/roll/lolco_4.jpg" />
    <img src="http://www.sibuya.co.kr/design/sibuya/2013new/roll/lolco_total_5.jpg" data-img="http://www.sibuya.co.kr/design/sibuya/2013new/roll/lolco_5.jpg" />
</div>

CSS

#main {
    float: left;
    width: 50%;
}

#gallery {
    float: left;
    width: 50%;
}

#gallery img {
    float: left;
    cursor: pointer;
}

JavaScript

$(function(){
    $("#gallery img").mouseenter(function(){
        var href = $(this).attr('data-img');
        $("#main img").attr('src', href);
    });
});