How do you extend the blank theme with a custom child theme?

[jornwildenbeest]

Hi,

I'm having some problems extending and using the blank theme.
First of all, I am kind of new to the extending theme's scene, so that is the reason it's probably not working.

I have the snowdog/theme-blank-sass installed using composer.
Then I created a child theme in app\design\frontend, having Snowdog/blank as parent in theme.xml
The child theme is called "theme-blank-child".

I've selected the new child theme in the settings in Magento.
When executing the yarn styles --theme basic-blank-child command, everything works fine with the default blank styles you get.

But now I'm having problems overriding / extending styles.

I tried adding a theme-blank-child/styles/styles.scss file, but it seems the it's not doing anything, because if I change the styles.css from the parent, it actually changes something. But updating the child styles.scss does nothing.

What is the right approach when overriding and extending the blank theme?