//
// Variables
// --------------------------------------------------
$embed-responsive-aspect-ratios: () !default;
$embed-responsive-aspect-ratios: join(
    (
        (21 9),
        (16 9),
        (4 3),
        (1 1),
    ),
    $embed-responsive-aspect-ratios
);

//
// Embed
// --------------------------------------------------
.embed-responsive {
    position: relative;
    display: block;
    width: 100%;
    padding: 0;
    overflow: hidden;
    &:before {
        display: block;
        content: "";
    }
    .embed-responsive-item,
    iframe,
    embed,
    object,
    video {
        position: absolute;
        top: 0;
        bottom: 0;
        left: 0;
        width: 100%;
        height: 100%;
        border: 0;
    }
}
@each $embed-responsive-aspect-ratio in $embed-responsive-aspect-ratios {
    $embed-responsive-aspect-ratio-x: nth($embed-responsive-aspect-ratio, 1);
    $embed-responsive-aspect-ratio-y: nth($embed-responsive-aspect-ratio, 2);
    .embed-responsive-#{$embed-responsive-aspect-ratio-x}by#{$embed-responsive-aspect-ratio-y} {
        &:before {
            padding-top: calc(100% * #{$embed-responsive-aspect-ratio-y} / #{$embed-responsive-aspect-ratio-x});
        }
    }
}