You can do it by adding required CSS in ‘Custom CSS’ option in AMP option panel>Design>Global https://prnt.sc/103e9ut. Add in the required CSS for the element you want to customize and click on save button.
Thanks
Sorry but I’m not expert in CCS.
Can you please provide me with a relevant link I can point to to learn about it?
Which elements correspond to H1 to H6 headers?
Can you follow this instructional tutorial (https://ampforwp.com/tutorials/article/how-to-change-font-style-in-amp/ ) and add CSS based on your requirements. And Then let us know back.
I really appreciate your help, i made the changes i wanted.
Thanks a lot