 is equal to the leaf path class value, then assign "current" class
                const doc = this.contentDocument.querySelectorAll("g." + currentID);
                // capture both arcs and lines of the current leaf
                for (let i = 0; i < doc.length; i++) {
                    // change the class to current for highlight
                    doc[i].classList = "leaf current";
                };
            });
        };//
        </script></html>