change status icon

  ->addColumn('enroll', function ($row) {
  $iconClass = $row->enroll === 1 ? 'far fa-check-circle text-success' : 'fa fa-exclamation-circle text-dark';

  $btn = '<a href="javascript:void(0)" class="enroll-toggle" data-id="' . $row->id . '" data-status="' . $row->enroll . '">';
      $btn .= '<i class="' . $iconClass . '"></i>';
      $btn .= '</a>';

  return $btn;
  })