JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.8/themes/base/jquery-ui.css">
<a id="button">Continue</a>

CSS

.my-button-icon {
    margin-left:10px; 
    display: inline-block;
    /*margin-top:10px; - not reliable*/
}

/* overwrite JQuery UI CSS to make the font larger */
.ui-widget {
    font-size: 150%;     
}

JavaScript

$("#button").append($("<span class='ui-icon ui-icon-circle-triangle-e my-button-icon'></span>")).button();