JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://masonry.desandro.com/jquery.masonry.min.js"></script>
<ul class="gallery masonry">
    <li class="item-wrapper">
        <div class="item-content"></div>
    </li>
    <li class="item-wrapper a1">
        <img src="http://upload.wikimedia.org/wikipedia/commons/thumb/0/0f/Artist%27s_Conception_of_Space_Station_Freedom_-_GPN-2003-00092.jpg/400px-Artist%27s_Conception_of_Space_Station_Freedom_-_GPN-2003-00092.jpg"/>
        <div class="tooltip">Blablabla tooltip</div>
    </li>
    <li class="item-wrapper a2">
        <img src="http://www.revisemri.com/tools/kspace/images/k_remlines.jpg"/>
                <div class="tooltip">Blablabla tooltip</div>
    </li>
<li class="item-wrapper a1">
        <img src="http://upload.wikimedia.org/wikipedia/commons/thumb/0/0f/Artist%27s_Conception_of_Space_Station_Freedom_-_GPN-2003-00092.jpg/400px-Artist%27s_Conception_of_Space_Station_Freedom_-_GPN-2003-00092.jpg"/>
        <div class="tooltip">Blablabla tooltip</div>
    </li>
    <li class="item-wrapper a2">
        <img src="http://www.revisemri.com/tools/kspace/images/k_remlines.jpg"/>
                <div class="tooltip">Blablabla tooltip</div>
    </li>
   <li class="item-wrapper a1">
        <img src="http://upload.wikimedia.org/wikipedia/commons/thumb/0/0f/Artist%27s_Conception_of_Space_Station_Freedom_-_GPN-2003-00092.jpg/400px-Artist%27s_Conception_of_Space_Station_Freedom_-_GPN-2003-00092.jpg"/>
        <div class="tooltip">Blablabla tooltip</div>
    </li>
      <li class="item-wrapper a2">
        <img src="http://www.revisemri.com/tools/kspace/images/k_remlines.jpg"/>
                <div class="tooltip">Blablabla tooltip</div>
    </li>
</ul>

CSS

ul {
    list-style:none;
    display:block;
    padding:0;     
}

.item-wrapper {
    position:relative;
    float:left;
    margin-left:5px;     
}

.tooltip {
    width:100px;
    height:auto;
    position:absolute;
    bottom:0;
    left:0;
    background:#ff0000;
    display:none;
}

.item-wrapper:hover .tooltip {
    display:block;
}

JavaScript

$(function(){
    
    var $container = $('.gallery');
    
    $container.imagesLoaded(function(){
      $container.masonry({
        itemSelector: '.item-wrapper',
        columnWidth: 5,
      });
    })
    
  });