feat: implement item selection functionality in exercise 3

clase-9.js

@@ -20,3 +20,15 @@ const charCount = document.getElementById('charCount');
 textInput.addEventListener('input', () => {
     charCount.textContent = textInput.value.length;
 });
+
+// Ejercicio 3
+
+const itemList = document.getElementById('itemList');
+
+itemList.addEventListener('click', (event) => {
+    if (event.target.tagName === 'LI') {
+        const items = itemList.querySelectorAll('li');
+        items.forEach(item => item.classList.remove('selected'));
+        event.target.classList.add('selected');
+    }
+});