/* default 16:9 aspect ratio */
.video-wrapper {
    position:relative;
    padding-bottom:56.25%;
    height:0;
}

/* 21:9 aspect ratio */
.video-wrapper.ar219 {
    padding-bottom:42.8571%;
}

/* 16:10 aspect ratio */
.video-wrapper.ar1610 {
	padding-bottom:62.5%;
}

/* 4:3 aspect ratio */
.video-wrapper.ar43 {
	padding-bottom:75%;
}

/* 1:1 aspect ratio */
.video-wrapper.ar11 {
	padding-bottom:100%;
}

/* span iframe */
.video-wrapper > * {
    position: absolute;
    top:0;
    left:0;
    width:100%;
    height:100%;
    border:none;
}