getStyle(elem, property = false) {
    let style
    if (window.getComputedStyle) {
      style = window.getComputedStyle(elem, null)
    } else if (elem.currentStyle) { //@ie-6 only feature
      style = elem.currentStyle
    }

    return property ? style[property] : style
  }
Get the computed style for DOM element @TODO Find usage?
@param  {Element}  elem     dom element
@param  {boolean} property style eg. width, height, opacity
@return {string}           computed style
@deprecated Function is not called anywhere