Mobile thumbnail to look like desktop thumbnail

Give this a shot:

@media (max-width: 768px) {
    body:not(.post-image-aligned-center) .featured-image, body:not(.post-image-aligned-center) .inside-article .featured-image {
        float: left;
        margin-right: 1.5em;
    }
}

The extra space on the left is the margin-left on the ordered list.

To remove it, try this:

ol {
    margin-left: 0;
}

I think we're done!

Happy w. your solutions :-)

Keep in touch!