mixin divider(level)
    -
        let classes = {
            'o-divider':                        true,
            'o-divider--labelled':              !!block,
            ['o-divider--' + level]:            true,
            ['o-divider--' + attributes.color]: !!attributes.color
        }

    div(class=classes)&attributes(attributes)
        if block
            .o-divider__label
                block