JSFiddle - React, Tailwind, and code Playground

HTML

<div class="font">
<img src="http://www.martinezcreativegroup.com/wp-content/uploads/2014/05/img-placeholder.png">
<img src="http://www.martinezcreativegroup.com/wp-content/uploads/2014/05/img-placeholder.png">
<img src="http://www.martinezcreativegroup.com/wp-content/uploads/2014/05/img-placeholder.png">
</div>

<div class="flex">
<div>
<img src="http://www.martinezcreativegroup.com/wp-content/uploads/2014/05/img-placeholder.png">
</div>
<div>
<img src="http://www.martinezcreativegroup.com/wp-content/uploads/2014/05/img-placeholder.png">
</div>
<div>
<img src="http://www.martinezcreativegroup.com/wp-content/uploads/2014/05/img-placeholder.png">
</div>
</div>

CSS

.font {
  width: 100%;
  font-size: 0;
}

.font img {
  display: inline-block;
  height: auto;
  margin: 1px;
  width: calc(33.333333% - 2px);
}

.flex {
  width: 100%;
  display: -webkit-box;
  display: -moz-box;
  display: -ms-flexbox;
  display: -webkit-flex;
  display: flex;  
}

.flex div {
  margin: 1px;
  width: 33.333333%;
}

.flex div img {
  width: 100%;
  height: auto;
  display: block;
}