.video-wrapper {
position: relative;
padding-bottom: 56.25%;
}
.video-wrapper iframe {
position: absolute;
width: 100%;
height: 100%;
top: 0;
left: 0;
}
/*
To Calculate the padding %age do the following:
Given the video with an aspect ratio of 16:9
padding-bottom: ((9/16) * 100) %
*/