Currently the SiteOrigin Video Player is not responsive. When I embed YouTube videos in my clients’ websites, I use this method to make them responsive: https://css-tricks.com/NetMag/FluidWidthVideo/Article-FluidWidthVideo.php
However, in order for my clients to add videos to their own website, they have to use SiteOrigin Video Player (not responsive) or I have to tell them to copy and paste my code and change the video source (not very efficient, especially for clients who aren’t tech-savvy).
Please make SiteOrigin Video Player responsive! :)