JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap-theme.min.css">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css">
<div class="container">
    <div class="row">
        <div class="col-md-6">
            <div class="panel panel-primary">
                <div class="panel-heading">
                    <h3 class="panel-title">
                        Panel 1</h3>
                    <span class="pull-right clickable collapse in"><i class="glyphicon glyphicon-plus"></i></span>
                </div>
                <div class="panel-body" >
                    Panel content</div>
            </div>
        </div>

        </div>
    </div>

CSS

.clickable
{
    cursor: pointer;
}

.clickable .glyphicon
{
    background: rgba(0, 0, 0, 0.15);
    display: inline-block;
    padding: 6px 12px;
    border-radius: 4px
}

.panel-heading span
{
    margin-top: -23px;
    font-size: 15px;
    margin-right: -9px;
}

JavaScript

$(document).on('click', '.panel-heading span.clickable', function (e) {
    var $this = $(this);
    if (!$this.hasClass('panel-collapsed')) {
    console.log($this);
    console.log("je suis dans le if");
        $this.parents('.panel').find('.panel-body').slideDown();
        $this.addClass('panel-collapsed');
        $this.find('i').removeClass('glyphicon-minus').addClass('glyphicon-plus');
    } else {
    console.log($this);
        console.log("je suis dans le else");
        $this.parents('.panel').find('.panel-body').slideUp();
        $this.removeClass('panel-collapsed');
        $this.find('i').removeClass('glyphicon-plus').addClass('glyphicon-minus');
    }
});