Change button alignement and size for mobile

11 hours ago, Erwan said:

- what would be the code or atribute to make them full page widht in mobile view?

You could try using the FILL setting in the button attributes, then you can control the size that way.

11 hours ago, Erwan said:

- why the organisation is switching in mobile? Like my name was first, then text then button on desktop. But that's the opposite in mobile view ... How can I correct this?

This sounds like you haven't edited the mobile layout. When editing the page click on the mobile toggle (top right) and edit how the blocks are arranged. This is something you have to do for every page, and adjust every time you make edits to a page.