.video {
    margin: 0 0 40px;
    overflow: hidden;
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
}

.video iframe,
.video object,
.video embed,
.video video {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}