diff --git a/01 - JavaScript Drum Kit/index-START.html b/01 - JavaScript Drum Kit/index-START.html
index 4070d32767..c047146df4 100644
--- a/01 - JavaScript Drum Kit/index-START.html
+++ b/01 - JavaScript Drum Kit/index-START.html
@@ -1,10 +1,12 @@
+
JS Drum Kit
+
@@ -57,10 +59,30 @@
-
+ key.classList.add('playing');
+ }
+
+ function removeTransition(e) {
+ if (e.propertyName !== 'transform') return;
+ this.classList.remove('playing');
+ }
+
+ const keys = document.querySelectorAll('.key');
+ keys.forEach(key => key.addEventListener('transitionend', removeTransition))
+ window.addEventListener('keydown', playSound);
+
-
+
+