Design themes (options)
The design settings enable customization of the appearance of each product options configuration. It is possible to edit variables such as colors, fonts, spacing, and more or provide custom CSS and JavaScript to further customize the product options design.
New product options configurations always use the Global default design theme:

The Local theme is only applied to the current configuration:

Design theme
The design theme includes the variables, custom CSS and JavaScript.
Sharing Local Design

You can create a new design theme based on the current local design settings. Click on the "+" Plus icon and give the new theme a name.
On your other product configurations, you can then select this theme as the default to use the same design settings.