Responsive Image in WordPress Visual Editor?

Question

Bootstrap

There is a WordPress entry made by the visual block editor. I add an image and it does not work to make it adaptive. If you choose percentages, (screen), then it may look ok for desktop, but not for mobile.

The site is on bootstrap, so I thought to add the img-fluid class to the block settings (screen),

but the class is applied to the div, which is already nested img, so nothing comes out.
Is it possible somehow to make images responsive without creating new classes and styles? Or the available WordPress tools or the bootstrap classes?

Answer 1

Your default style should always be
img { max-width: 100% }