center iframe {
    width: 100%;
    height: calc(100vw * 9 / 16 );
}

var setResponsive = function () {
  if ($(window).height() > $("#adminmenuwrap").height() + 50) {
     $('#adminmenuwrap').css('position', 'fixed'); 
  } else {
     $('#adminmenuwrap').css('position', 'relative'); 
  }
}
$(window).resize(setResponsive);
setResponsive();