('click', function() {
                        const format = formatSelect.value;
                        downloadMindmap(format);
                    });
                }

                closeBtn.addEventListener('click', function () {
                    popup.style.display = 'none';
                });

                popup.addEventListener('click', function (event) {
                    if (event.target === popup) {
                        popup.style.display = 'none';
                    }
         