left: (
                pos.left +                                                                // The absolute mouse position
                this.offset.relative.left * mod +                                        // Only for relative positioned nodes: Relative offset from element to offset parent
                this.offset.parent.left * mod    -                                        // The offsetParent's offset without borders (offset + border)
                ( ( this.cssPosition === "fixed" ? -this.scrollParent.scrollLeft() : scrollIsRootNode ? 0 : scroll.scrollLeft() ) * mod)