Wrap oembeds with containing div and according styles for fluid videos in responsive design

fluid-oembed.css

/* OEMBED
-------------------- */      
.oembed-container {
	position: relative;
	height: 0;
	margin-top: 1em;
	padding-bottom: 56.25%;
	overflow: hidden;
} 
.oembed-container iframe,  
.oembed-container object,  
.oembed-container embed {
	position: absolute;
	top: 0;
	left: 0;
	width: 100%;
	height: 100%;
}

gistfile1.aw

add_filter( 'oembed_dataparse', 'zero_embed_wrapper', 90, 3 );
/**
 * Filters output of oembed to wrap with a div to help with fluid video embeds.
 *
 * @since zero 0.5.1
 */
function zero_embed_wrapper( $output, $data, $url ) {
  return '<div class="oembed-container">' . $output . '</div>';
}