.embed-responsive{

    position: relative;
display: block;
width: 100%;
padding: 0;
overflow: hidden;
}

.embed-responsive::before{
    display: block;
content: "";
}

.embed-responsive .embed-responsive-item, .embed-responsive embed, .embed-responsive iframe, .embed-responsive object, .embed-responsive video{
    position: absolute;
top: 0;
bottom: 0;
left: 0;
width: 100%;
height: 100%;
border: 0;
}

.embed-responsive-16by9::before{
    padding-top: 56.25%;
}