Yes, the widget has custom selectors that you can use to change how it appears and we provide an area within the app where you can add your own CSS.
We do however have very good survey response rates on the Order Status Page and we put this down to the widget having a neutral style and appearing to be an integral part of the page.
If you'd still like to make changes to the style of the widget, please take a look at our article on styling the grapevine survey widget.