Ratio

Ratio calculates the ratio based on the width of the element. This way you can get basic ratio settings like 16/9. Pseudo will be false as default, setting it to true adds the ratio as a before pseudo to the element.

HTML: 

             <span class="mixin-example-ratio">_</span>

SCSS: 

        .mixin-example-ratio {
            @include ratio(16, 2);
        }