JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="//maxcdn.bootstrapcdn.com/font-awesome/4.3.0/css/font-awesome.min.css">
<button type="button" class="btn btn-sm btn-default" >save <span class="fa fa-caret-down bottom-right"></span></button>

CSS

button {
    width: 200px;
    height: 100px;
    position: relative;
}

.bottom-right {
    position: absolute;
    bottom: 0px;
    right: 0px;
}