commit 26179adbf871c7bdc22c332c23dd4c047c4f5104
Author: ronny abraham <ronny.abraham@ymail.com>
Date:   Fri Jun 13 00:41:01 2025 +0300

    add collapsible

diff --git a/collapsible.js b/collapsible.js
new file mode 100644
index 0000000..ded1a8a
--- /dev/null
+++ b/collapsible.js
@@ -0,0 +1,17 @@
+document.addEventListener('DOMContentLoaded', function() {
+  var headers = document.querySelectorAll('h4');
+
+  headers.forEach(function(header) {
+    header.addEventListener('click', function() {
+      var nextElement = header.nextElementSibling;
+      if (nextElement) {
+        var collapsibleList = nextElement.querySelector('.playlist, .notes, .contents');
+        if (collapsibleList) {
+          header.classList.toggle('active');
+          collapsibleList.classList.toggle('active');
+        }
+      }
+    });
+  });
+});
+