How to make native video player full width?

This is what I have now:

I want the video player to take up the whole horizontal space and stretch width 100%. The video should also stay responsive, filling the whole video player area.

I fallowed advice in this answer and added this to my functions.php:

if ( ! isset( $content_width ) ) {
$content_width = 850; }

The content width on my template is 850px. But setting the content width didn’t help.

How to make WordPress native video player width 100%?

I added this to my style.css and now the video player is fully responsive!

.wp-video, video.wp-video-shortcode, .mejs-container, .mejs-overlay.load {
    width: 100% !important;
    height: 100% !important;
}
.mejs-container {
    padding-top: 56.25%;
}
.wp-video, video.wp-video-shortcode {
    max-width: 100% !important;
}
video.wp-video-shortcode {
    position: relative;
}
.mejs-mediaelement {
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
}
.mejs-controls {
    display: none;
}
.mejs-overlay-play {
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    width: auto !important;
    height: auto !important;
}