How to include vendor/magento/module-page-builder Page Builder styles in custom theme?

Hi, we’ve just updated to M2.4.3p1 Open Source and part of the reason was to get Page Builder, which we now have, so that’s great.
But… we can’t work out how to include the styles from the Page Builder in our custom theme. If we swap to Luma theme then the styles are there as expected, but in our theme the styling is missing.

We understood that in M2 themes, everything was included as default and you had to set exceptions if you didn’t want something to appear or be included, but we don’t see any exclusions for Page Builder.

Is there something obvious we might be missing?

Thanks,

James