.embed-responsive-15by16{aspect-ratio:15/16}.embed-responsive-15by16::before{padding-top:106.67%}.embed-responsive-16by7{aspect-ratio:16/7}.embed-responsive-16by7::before{padding-top:43.75%}.embed-responsive-4by3{aspect-ratio:4/3}.embed-responsive-4by3::before{padding-top:75.00%}