JSFiddle - React, Tailwind, and code Playground

HTML

<script src="//netdna.bootstrapcdn.com/twitter-bootstrap/2.3.1/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="//netdna.bootstrapcdn.com/twitter-bootstrap/2.3.1/css/bootstrap-combined.min.css">
<div class="row-fluid summary">
    <div class="span11">
        <h2>MyHeading</h2>  
    </div>
    <div class="span1">
        <button class="btn btn-success collapsed" data-toggle="collapse" data-target="#intro"></button>
    </div>
</div>
<div class="row-fluid summary">
    <div id="intro" class="collapse"> 
        Here comes the text...
    </div>
</div>

CSS

button.btn.collapsed:before
{
    content:'+' ;
    display:block;
    width:15px;
}
button.btn:before
{
    content:'-' ;
    display:block;
    width:15px;
}