Function getOffsetParent

src/prototype/dom/layout.js:1052–1076

* Element.getOffsetParent(@element) -> Element * * Returns `element`'s closest _positioned_ ancestor. If none is found, the * `body` element is returned.

(element)

   *  `body` element is returned.
  **/
  function getOffsetParent(element) {
    element = $(element);

    // Ensure we never return the root HTML tag.
    function selfOrBody(element) {
      return isHtml(element) ? $(document.body) : $(element);
    }

    // For unusual cases like these, we standardize on returning the BODY
    // element as the offset parent.
    if (isDocument(element) || isDetached(element) || isBody(element) || isHtml(element))
      return $(document.body);

    // IE reports offset parent incorrectly for inline elements.
    var isInline = (Element.getStyle(element, 'display') === 'inline');
    if (!isInline && element.offsetParent) return selfOrBody(element.offsetParent);

    while ((element = element.parentNode) && element !== document.body) {
      if (Element.getStyle(element, 'position') !== 'static') {
        return selfOrBody(element);
      }
    }

    return $(document.body);
  }


  /**