How to add close button to bootstrap card?
This isn't a standard feature of bootstrap, so you need to bind a JS click event to the icon, and trigger it to close the parent .card. I also added cursor: pointer to the icon so that it looks like something you can click on.
$('.close-icon').on('click',function() {
$(this).closest('.card').fadeOut();
}).close-icon {
cursor: pointer;
}<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet"/>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet"/>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<div class="card card-outline-danger text-center">
<span class="pull-right clickable close-icon" data-effect="fadeOut"><i class="fa fa-times"></i></span>
<div class="card-block">
<blockquote class="card-blockquote">
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p>
<footer>Someone famous in <cite title="Source Title">Source Title</cite></footer>
</blockquote>
</div>
</div>