Once you have set up the ScandiPWA theme, you can customize it to your needs. For this, you can use the Override Mechanism, which lets you override parts of the ScandiPWA theme while keeping the default implementation for the rest.
We recommend the following workflow to get started with theme cusomization:
Start by overriding the base styles to define the general look and feel of your application (theme colors, font sizes, spacing, etc)
Override any other components that you wish to adjust
If you plan to develop a reusable extension instead of customizing a single theme, consider developing an extension instead.