How to display view on ajax request so that the form works on it?

Question

Yii

I want to make the registration form appear on the site with Ajax when a button is clicked.
It turns out I need to display a view with a form on top of the index
Here is the js code when the register button is pressed

let regButton = document.querySelector('#reg_button');
regButton.onclick = function (e) {
  e.preventDefault();
  $.ajax({
    type: "POST",
    url: "site/reg",
    success: function (response) {
      $('#response').html(response)
    },
    error: function (response) {
      console.log(response)
    }
  });
};

Here is the code of the action that handles the request

public function actionReg()
  {
    if (Yii::$app->request->isAjax) {
      Yii::$app->response->format = Response::FORMAT_JSON;
      $model = new RegForm();
      return $this->renderAjax('reg', compact('model'));
    }
  }

As a result, it turns out that the answer is displayed and the form appears,
BUT it is without styles and scripts processing validation