I have a JSFiddle here - http://jsfiddle.net/n90Lexgc/
I'm using bootstrap modal to load a vimeo video.
I've added CSS to make the video larger and responsive.
My problem is I've lost the play button in the video.
If I click the video it plays and stops, but I have no play button.
<!-- video player -->
<div id="myModal" class="modal fade" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
<div class="modal-dialog">
<div class="modal-content embed-responsive embed-responsive-16by9">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
</div>
<div class="modal-body">
<iframe width="1000" height="528" frameborder="0" allowfullscreen="" class="embed-responsive-item"></iframe>
</div>
</div>
</div>
</div>
<!-- video player -->
<div class="container-fluid">
<div clas="row">
<button class="js-play" data-vid="105100455">Video</button>
</div>
</div>
Its not that your buttons are missing, they're just pushed so far down you can't see them.
You'll need to cut some of the padding from your modal-body.
.modal-body {
...
padding-bottom: 49%;
...
}