Problem : Banners display on mobile

Site URL: https://oriole-cowbell-8s27.squarespace.com/

Password to access the website : sophrologie

HI, 

I have issues with the display of my banners and images. 

1) My banners on the first page (welcome page) are rectangular and on the laptop display it's ok but on mobile it's only part of the images that display. 

And it looks weird because my images are cut. Can i choose a different banner just for the mobile version ? 

2) On the page sophrology, one of my image appears very big in the center while on the laptop, it displays in two columns. 

Thanks in advance 

(my english isn't very good... hope it will be ok:) )

i have find a way with the focal point. I changed it.