#containingBlock {
    width: 50%;
}
 
.videoWrapper {
    position: relative;
    padding-bottom: 56.25%;
    padding-top: 25px;
    height: 0;
}
 
object,
embed {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}