Even when this demo preloads both images (desktop & mobile) it will load a small blurred image (16x16) for the one that doesn't match screen width
specified in the sizes attribute.
Uses Nextjs <Image/>component.
The smaller image is configured to render only screens smaller than 768px via the sizes attribute.
The bigger image is configured to render only on screens bigger than 768px via the sizes attribute.
Both images use the priority attribute to enable prefetching.
Additional CSS code is added to hide the corresponding image beased on media queries.