.grav-youtube {
    height: 0;
    padding-top: 25px;
    padding-bottom: 56.34%;
    margin-bottom: 10px;
    position: relative;
    overflow: hidden;
    max-width: 1920px;
    max-height: 1080px;
}

.grav-youtube iframe {
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    position: absolute;
}