Hello ameyban,
Thank you so much for using our theme Mercantile.
Depends on what you understand by responsive. The slider is full screen regardless of screen size and the images (actually background images) are set to cover that certain screen size. Obviously, that means some parts of the image will be cropped because your image sizes won’t be the same as the device size. Hope you understand what we mean. Can you please add the image we used on demo and check once.
Thank you