Single masonary grid in mobile portfolio results in blury images

Good day,

I was trying to use this code to get single column on masonary grid while on mobile:

/* Masonry one item on mobile */
@media screen and (max-width:767px) {
.gallery-masonry-item-wrapper {
height: auto !important;
margin-bottom: 30px !important;
}
figure.gallery-masonry-item {
position: relative !important;
width: 100% !important;
transform: unset !important;
}
.gallery-masonry-item-wrapper {
height: auto !important;
}
.gallery-masonry .gallery-masonry-item[data-loaded] img {
width: 100% !important;
}
.gallery-masonry {
padding-left: 10 !important;
padding-right: 10 !important;
}
/* new code */
.gallery-masonry-wrapper.gallery-masonry-list--ready {
    height: auto !important;
}}

It works however I noticed that the images themselves are very low res, much lower res than the upload, and after trying to trouble shoot I figured its always like that whenever I change to one column in the section settings on mobile. Do you know why is that and how to get around this? Also, I cannot use code injection tools since its a personal plan.

Thanks a lot

Darius

Can you share link to page where you use masonry?