public function store(Request $request)
    {
        $this->validate($request, [
            'theme' => 'required',
        ]);

        /** @var Configuration $config */
        $config        = Configuration::query()->firstOrCreate(['key' => 'theme.frontend']);
        $config->value = $request->get('theme');
        $config->save();

        flash()->success(trans('cms::theme.success', ['theme' => $request->get('theme')]));

        return back();
    }