Bootstrap 3 Skeleton

This is a simple Bootstrap skeleton. You can fork it to get a ready to use Bootstrap fiddle.

HTML

<script src="http://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/2.1.0/bootstrap.min.js"></script>
<div class="row">
    <div id="divA" class="col-sm-12 col-lg-3 bg-warning">
        A
    </div>
    <div id="divB" class="col-sm-12 col-lg-9 bg-danger">
        B
    </div>      
</div>

CSS

@import url('http://getbootstrap.com/dist/css/bootstrap.css');

JavaScript

$(document).ready(function(){
    if ($(window).width() < 768){
      
       $("button").click(function(){
    $("<span>Hello world!</span>").insertBefore("p");
});
    }
    else {
        
    }
});