Mobile Body Background image

I have to use the same wallpaper for mobile and tablet as for the desktop view. (For the body! -> background image)
In Elementor you can use a different image for the different views. However, that doesn’t work.

The image is an svg file. The image should not be moved when scrolling. Is there a way to do this? And it should be fullscreen. So occupy the screen area of ??tablet and smartphone without being distorted or too big.