JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css">
<script src="http://netdna.bootstrapcdn.com/bootstrap/3.0.0/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="http://netdna.bootstrapcdn.com/font-awesome/3.2.1/css/font-awesome.min.css">
<span><input type="submit" value="Send" class="btn btn-default" /></span>

CSS

input[type="submit"] {
    margin: 10px;
    padding-right: 30px;
}

span {
    position: relative;
}

span:after {
    font-family: FontAwesome;
    content: "\f004";
    font-size: 13px;
    position: absolute;
    right: 20px;
    top: 1px;
}