JSFiddle - React, Tailwind, and code Playground

HTML

<div class="foo">
		<img src="http://s29.postimg.org/z632s2x1z/shark.jpg" alt="">
		<img src="http://s29.postimg.org/z632s2x1z/shark.jpg" alt="">
		<img src="http://s29.postimg.org/z632s2x1z/shark.jpg" alt="">
		<img src="http://s29.postimg.org/z632s2x1z/shark.jpg" alt="">
            <div class="clear"></div>
	</div>

CSS

body {
    margin: 0;
    padding: 0;
}
.foo {
    width: 100%;
    height: 100%;
    background: #999;
    box-sizing: border-box;
    padding: .5%;
}
img {
    width: 50%;
    float: left;
    padding: .5%;
    box-sizing: border-box;
}
.clear {
    clear: both
}