style youtube embed video css

1//Add the following CSS to your code
2
3
4.iframe-container{
5  position: relative;
6  width: 100%;
7  padding-bottom: 56.25%; 
8  height: 0;
9}
10.iframe-container iframe{
11  position: absolute;
12  top:0;
13  left: 0;
14  width: 100%;
15  height: 100%;
16}