apply (slides) {
      for (let i = 0, len = slides.length; i < len; i++) {
        const style = slides[i].style
        const direction = Components.Direction.value

        if (i !== 0) {
          style[MARGIN_TYPE[direction][0]] = `${this.value / 2}px`
        } else {
          style[MARGIN_TYPE[direction][0]] = ''
        }

        if (i !== slides.length - 1) {
          style[MARGIN_TYPE[direction][1]] = `${this.value / 2}px`
        } else {
          style[MARGIN_TYPE[direction][1]] = ''
        }
      }
    }
Applies gaps between slides. First and last
slides do not receive it's edge margins.

@param {HTMLCollection} slides
@return {Void}