Images not working on mobile

Hi,
I have been working on my website and there’s an issue is getting all the background images to load on mobile, but they don’t all load on the real mobile.
but It’s worked when I toggle the device on chrome, every kinda device is worked.
I am wondering how should I fix this?

this’s how looks like on chrome mobile and on my phone or any other people’s phone.

my page:https://zoeyyingying.github.io/
my github:https://github.com/ZoeyYingying/ZoeyYingying.github.io

Thx
Zoey