JSFiddle - React, Tailwind, and code Playground

HTML

<div class="imghover"><img src="http://i.imgur.com/7gmiGeF.jpg"/></div>

CSS

.imghover{background:#14789B}
.imghover,.imghover img{float:left}
.imghover img:hover{opacity:.7;-moz-opacity:.7;-o-opacity:.7;-webkit-opacity:.7;-ms-opacity:.7}