if ( !o.axis || o.axis !== "x" ) {
                if ( ( i.overflowOffset.top + scrollParent.offsetHeight ) - event.pageY < o.scrollSensitivity ) {
                    scrollParent.scrollTop = scrolled = scrollParent.scrollTop + o.scrollSpeed;
                } else if ( event.pageY - i.overflowOffset.top < o.scrollSensitivity ) {
                    scrollParent.scrollTop = scrolled = scrollParent.scrollTop - o.scrollSpeed;