function getStyle(element, style) {
    var styles = cache$1 && cache$1.get(element);

    if (!styles) {
      styles = window.getComputedStyle(element, null);
      if (cache$1) cache$1.set(element, styles);
    }

    return styles.getPropertyValue(style);
  }
Returns the computed value of an element's style property as a string.

@param {HTMLElement} element
@param {String} style
@returns {String}