How to make a YouTube embedded video a full page width one?

Here's a FIDDLE

<iframe id="video" src="//www.youtube.com/embed/5iiPC-VGFLU" frameborder="0" allowfullscreen></iframe>


$(function(){
  $('#video').css({ width: $(window).innerWidth() + 'px', height: $(window).innerHeight() + 'px' });

  // If you want to keep full screen on window resize
  $(window).resize(function(){
    $('#video').css({ width: $(window).innerWidth() + 'px', height: $(window).innerHeight() + 'px' });
  });
});

Correct style for your iframe

iframe {
    position: fixed;
    right: 0;
    bottom: 0;
    min-width: 100%;
    min-height: 100%;
    width: auto;
    height: auto;
}