How to stack 'Grid' section on mobile instead of 2 in a row/carousel - Palo Alto Theme

Desktop and mobile view showing above

On mobile it goes too small, we would like the ‘Grid’ to stack instead on mobile view but there is no inbuilt option.

I have limited coding knowledge (I am learning) but I guess it would involve editing the ‘2 in a row’ mobile option to 1?

How could I edit this, or will it involve editing other areas of the code too? Is it styling within css?

Below is the option in the theme editor:

Thank you in advance for any one that can talk me through this as I really want to learn!