Image get cropped on mobile version

I use :

Theme: Customizr
Beaver Builder Plugin (Lite Version)

Site : Prisma Renders

Problem :

The gallery is not mobile friendly…

When using the default configurations, the gallery resizes my site because it does not resize itself properly… So instead of just scrolling vertically only, it scrolls horizontally too… And the rest of the contents gets messed up…

On the image below, you see on the top the Image slider from the Cutomizr theme witch is meant to take the hole page width. But it doesn′t when using the image galley (right below it, same page).

Then, if i use the option on the Beaver Builder Plugin to resize the gallery on small screens, the images get cropped and does not get centered… another mess…

You see on the image below, that now the Customizr slider works properly cause the page no longer was resized, but you can see the images get cropped (if you check the previous image, you see a wood panel on the bigest pic), and are not centered.