.iframe-container {
    position: relative;
    padding-bottom:56.25%;
    height:0;
    overflow:hidden;
    margin: 40px auto;
    max-width:788px;
}
.generated-iframe iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

@media screen and (min-width:1280px){
    .iframe-container {
        margin: 80px auto;
    }
}