Change from multiple cards display to single card display in a slider on mobile view

How do I create a multiple card display (i.e. 2 rows of 3) to single slider card display on mobile view?

There was this video tutorial: - Unfortunately I cannot change the Mask to be a flexbox as he has mentioned - Webflow must have changed the system since.

Here is my site Read-Only:
I was looking to do this in ‘Featured Services’ section.