You can add custom css style. This mean that you can customize design of the website for your own neads. Just add style tag inside that custom script cell it will work.

For example you might want to center extra fields in the detailed pages 

<style>
    .detailed-page-extra-fields-all {
        text-align: center
    }
</style>

How to add custom CSS style to your website

  1. Open your Google Sheet
  2. Advanced tab
  3. Custom Javascript (it's using the same cell for styles as for scripts.)