.zfv {
position: relative;
padding-bottom: 56.25%;
padding-top: 25px;
height: 0;
}
.zfv_archive {
margin: -.7em -1.2em 13px;
}
.zfv iframe {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
}