Dev theme from site library loosing style when child theme is enabled

Hi,

So, I am creating a website with GP Premium and the "Dev" theme from Mike Oliver (site library). I installed the child theme from here: https://docs.generatepress.com/article/using-child-theme/ but it seems that the child is breaking the styling, for example the buttons floating effect and the inline styling in the newsletter form are no longer effective. Probably elsewhere also, although these are the points I noticed.

I am developing this website locally and so I am unable to share a live link unfortunately.

Please advise.

Thanks!