Fullwidth Easy Slider: images are shown completely also on mobile

Hi folks, I’d like to reproduce the behaviour of the Fullwidth Easy Slider component that you used in the DJ Enfold demo homepage.
That Fullwidth slider is using two 1030×412 very wide pictures: when you browse that homepage from a mobile phone (in portrait mode, of course), it shows only the central portion of the image, making the image tall enough to show the included headings & the button.

I’ve tried to do the same, but when I see my Fullwidth Easy Slider on a mobile phone, it is showing me the WHOLE picture, and not only the central part. The result is that the whole image is not tall enough to include the button: the heading is there, but the button cannot be contained in such a small space, and it is not visible.

I thought it was an issue with my images, therefore I’ve used the same images of the demo, and I’ve got the same result: the images are fully visible.
in the “Styling” tab of my Fullwidth Easy Slider element I’ve used the same configuration of your demo, i.e. “No scaling (Original Width X Original Height)” & “Yes, stretch the image”.
Where is my mistake?

Thanks folks!
Bye,
A.-