How can I make the videos responsive on mobile in posts? Example URL: http://krzysztofblas.com/2016/04/15/polski-krzysztof-blas-w-duecie-z-michalem-kowalonkiem-na-targach-musicmesse-we-frankfurcie-2/

I have a problem. If I put a video, smartphones do not see anything only a blank space. Thanks, Nicolò

I would make my embedded videos from youtube are responsive could help me with this please ?. Cheers