Hi,
I've checked your link but that's not what I see:
take.ms/sX1kU
For me, it's as if the "use bootstrap design" setting of the HikaShop configuration was turned off, and thus the elements of the listing are not changed to one per row on mobile.
Regarding the width of the images of a listing, by default, it's fixed based on what you set in the settings, regardless of where you display it. If you want the image size to adapt, some additional custom CSS might be required, but the exact CSS code will depend on how the page display, the CSS of the template. As I can't reproduce what you're talking about, I can't give a precise answer.