JSFiddle - React, Tailwind, and code Playground

HTML

<section class="one_third service clearfix">
<figure class="service-icon"> <img src="images/colorschemes/green/service1.png" alt="Fresh & Clean"></figure>
<article class="service">
<h3> Fresh & Clean Design </h3>
<p>Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. </p>
<a href="#" class="excerpt" target="_self">Learn More</a> </article>
</section>                                                        
                                                                      <section class="one_third service clearfix">
<figure class="service-icon"> <img src="images/colorschemes/green/service1.png" alt="Fresh & Clean"></figure>
<article class="service">
<h3> Fresh & Clean Design </h3>
<p>Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. </p>
<a href="#" class="excerpt" target="_self">Learn More</a> </article>
</section>
                                                                         
                                                                       <section class="one_third service clearfix">
<figure class="service-icon"> <img src="images/colorschemes/green/service1.png" alt="Fresh & Clean"></figure>
<article class="service">
<h3> Fresh & Clean Design </h3>
<p>Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. </p>
<a href="#" class="excerpt" target="_self">Learn More</a> </article>
</section>

CSS

.last{background:red; color:#fff;}

JavaScript

$('.one_third:last-child').addClass('last');