Bootstrap 3 Template
This is a simple Twitter Bootstrap 3 template. You can fork it to get a ready to use Bootstrap 3 fiddle.
HTML
<script src="//netdna.bootstrapcdn.com/bootstrap/3.0.0/js/bootstrap.min.js"></script>
<script src="https://code.jquery.com/jquery-2.1.4.min.js"></script>
<link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css">
<script src="https://cdn.rawgit.com/nnattawat/flip/master/dist/jquery.flip.min.js"></script>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.0/css/bootstrap.min.css">
<div class="modal in" id="send_message_modal" tabindex="-1" role="dialog" aria-hidden="true" style="display:block">
<div class="modal-dialog">
<div class="modal-content">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
<h4 class="modal-title">Send Message</h4>
</div>
<div class="modal-body">
<form role="form" id="send_message_form">
<div class="callout callout-danger error_message" style="display:none"></div>
<div class="form-group">
<label for="send_message_recipient">RECIPIENT</label>
<div class="input-group">
<input type="text" class="form-control" name="recipient" id="send_message_recipient" placeholder="Recipient Account" autofocus tabindex="1" />
<span class="input-group-btn btn-group recipient_selector">
<button type="button" class="btn btn-default dropdown-toggle" data-toggle="dropdown"><span class="glyphicon glyphicon-user"></span></button> <ul class="dropdown-menu scrollable-menu" role="menu" style="right:0;left:auto;"></ul>
</span>
</div>
</div>
<div class="form-group">
<label for="send_message_message">MESSAGE</label>
<textarea class="form-control" id="send_message_message" name="message" rows="4" tabindex="2"></textarea>
</div>
</form>
</div>
<div class="modal-footer" style="margin-top:0;">
<div...
CSS
/* Latest compiled and minified CSS included as External Resource*/
/* Optional theme */
@import url('//netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap-theme.min.css');
body {
margin: 10px;
}