.aspect-ratio(@width, @height) {
    @ratio: (@height / @width);
    height: 0;
    padding-top: (100% * @ratio);
}

.aspect-ratio-target(@width, @height, @target: '> *') {
    @target-escaped: ~'@{target}';
    position: relative;

    &:before {
        content: '';
        display: block;
        .aspect-ratio(@width, @height);
    }

    @{target-escaped} {
        .position();
    }
}