Yes, when you gradually reduce the width of your browser window on a PC, there are points where the design changes. In Wix Studio, however, your site is automatically optimized to display the best layout for each device size. I checked your site on an iPhone, and it looks almost the same as on a PC. However, the way the images appear—the visible area—differs.
If by saying you want the same appearance on PC, tablet, and iPhone you mean that the entire image should always be visible on every device, then you would need to edit the breakpoints for smaller devices, such as tablets and iPhones. Most likely, reducing the height of each section where the image is applied would allow the full width of the image to be displayed. Alternatively, you may need to adjust the “fit option” for the images.
That said, before doing so, it’s worth considering whether this approach is truly optimal for smaller devices.