Create js/script.js

static/js/script.js

@@ -0,0 +1,13 @@
+// static/js/script.js
+document.addEventListener('DOMContentLoaded', () => {
+    const form = document.querySelector('form');
+    if (form) {
+        form.addEventListener('submit', (e) => {
+            const fileInput = document.querySelector('input[type="file"]');
+            if (!fileInput.files.length) {
+                e.preventDefault();
+                alert('Please select a video file.');
+            }
+        });
+    }
+});