Enable CORS

exam/classes/Api/Api.php

@@ -8,6 +8,10 @@ class Api
 {
   public function __construct()
   {
-    Response::response()->header("Cache-control: no-cache");
+    Response::response()
+      ->header("Cache-control: no-cache")
+      ->header("Access-Control-Allow-Origin: *")
+      ->header("Access-Control-Allow-Methods: *")
+      ->header("Access-Control-Allow-Headers: *");
   }
 }