Okay, two approaches…
1) Just now realizing the “out of the box” the plugin doesn’t wrap the iframe in a container div, making it a bit harder than ideal to target via CSS.
I’ve updated the plugin to do so, but it might not get pushed out for a bit.
If you want to “hack” the plugin until such time as an update gets pushed, you can go into the file “class-tube-vc-embed.php” and add a wrapper div…
BEFORE (Lines 61 – 70)
// get the embed code for the video
$video_embed = $this -> get_video_embed( $post->ID );
if ( ! $video_embed ):
return $content;
endif;
// get the video placement option
$video_placement = get_option( 'tube_vc_video_placement' );
AFTER (Lines 61 – 73)
// get the embed code for the video
$video_embed = $this -> get_video_embed( $post->ID );
if ( ! $video_embed ):
return $content;
endif;
// wrap the video in a div
$video_embed = '<div class="tube-video-wrap">' . $video_embed . '</div>';
// get the video placement option
$video_placement = get_option( 'tube_vc_video_placement' );
Then, go into “Appearance > Customizer > Additional CSS” or your child theme’s CSS and add the following which will assume 16×9 videos…
.tube-video-wrap {
position: relative;
padding-bottom: 56.25%;
padding-top: 30px;
height: 0;
overflow: hidden;
}
.tube-video-wrap iframe {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
}
2) [ALTERNATIVE SOLUTION] I believe if you install the wonderful iFramely plugin it’ll make your videos responsive without doing anything more.