You could try the follow

.img {
border: none;
}

Or

.page-content img, .entry-content img {
border: none;
}

If neither of the above work try:

.page-content img, .entry-content img {
border: none!important;
}

If that works you’ll need to find the right class/id to target as the styles inheriting from somewhere else. It’s not ideal to use “!important” but it’s not the end of the world if you use it

Hope that helps

Great work.

At a bit of a loss here

Cheers

picture.alignright {
    border: None;
}

To add or override CSS: use the “Additional CSS” option in the customizer. https://codex.www.ads-software.com/CSS#Custom_CSS_in_WordPress

Learn to use the Chrome Developer Tools to help you see and test changes to your CSS.

.alignright, img.alignright {
border: none;
}

Hope that helps

All borders have gone and it’s looking normal. Cheers.