Same problem with responsive layout

Hi,
i have see there some problem with responsive layout in https://www.saldatura.com/
and in details:
a. slidable in portrait view in tablet and smartphone, see the screenshot:
https://www.dropbox.com/s/dqp497zwsnah8u1/portrait-slideble-phone.png?dl=0
https://www.dropbox.com/s/0gplp8nskozatks/portrait-slideble-tablet.png?dl=0
the content is not correct align.
b. the grid post default in portrait view in phone, see the screenshot:
https://www.dropbox.com/s/qhvueqb3jb04glm/portrait-phone.png?dl=0
https://www.dropbox.com/s/npgg8tjy07tqcsh/grid-post-portrait-tablet.png?dl=0
How i can to create a different “postgrid default” for a different output?

Thx for your help.
Davide