Grid spacing – css .uagb-post__image

Hi quick question on 2 widths kindle/tablet width and phone

This offsets my image to line up with text on right and left but every time the cache is deleted the id dc26b963 keeps changing and goes back to the previous state?

@media only screen and (max-width: 976px) {
.uagb-block-dc26b963.is-grid .uagb-post__inner-wrap .uagb-post__image:first-child {
margin-left: -20px!important;
margin-right: -20px!important;
margin-top: 0;
}
}

@media only screen and (max-width: 767px) {
.uagb-block-dc26b963.is-grid .uagb-post__inner-wrap .uagb-post__image:first-child {
margin-left: -20px!important;
margin-right: -20px!important;
}
}

Can I use the image css rule below instead so it doesn’t keep changing?

@media only screen and (max-width: 976px) {
.uagb-post__image:first-child {
margin-left: -20px!important;
margin-right: -20px!important;
margin-top: 0;
}
}

@media only screen and (max-width: 767px) {
.uagb-post__image:first-child {
margin-left: -20px!important;
margin-right: -20px!important;
}
}

Many Thanks

Jason

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