Hi there,
a lot of mobile devices will NOT support fixed background images as it requires a lot of processing power and therefore consumes a lot of battery. So the device disables the fixed background… and on iOS there is a many year old Bug that causes the image to be rescaled to a huge size.
The fix is to disable the fixed background images on touch devices using some CSS:
@media (pointer: coarse) {
.gb-container {
background-attachment: inital !important;
}
}