there is a gray bar showing under parallaxing images on the mobile version.
Attached files: parallax.PNG paralax1.PNG
It is because the image isn't big enough.
Since the raw ratio is totally different, the height of your image is not enough to create a parallax.
Parallax are hard to get working on all devices using the same raw and images.
Do not hesitate to contact us if you have more questions.
Have a nice day!
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