Thank you again! This additional code for the padding-top fixed the inconsistency with the top padding.
I didn't end up using the border-radius code because while it did make the image a circle on chapter 133, it also affected the other chapters (which have square images). This part isn't a big deal to me, so at this point I'm happy with the code, but if you discover a way to maintain the image shape design on mobile while using this code, then I welcome the support!
Thanks again for all your help! You are such an incredible resource for us here in the Squarespace community.
For anyone else who may see this, this is the final code I used that worked for me:
@media screen and (max-width:767px) {
div.horizontalrule-block + .row .image-block svg {
display: none;
}
div.horizontalrule-block + .row div.image-block.sqs-block, div.horizontalrule-block + div.image-block.sqs-block {
padding-top: 0px !important;
}
}