Header postion specific page on mobile

dear support,

i try to shift the background-image position of a color-section a little to the left on a specific page on mobile with the following css. But it takes no effect.
What am i doing wrong?

@media only screen and (max-width:767px) {
	.page-id-9218 .avia-section.av-l7ssci9u-16e3a1176082f93cc0959288649b4b4a {
	background-position: 35% 50% !important;
	}
}