Images
Documentation and examples for opting images into responsive behavior (so they never become wider than their parent) and add lightweight styles to them—all via classes.
Responsive images
Images in Bootstrap are made responsive with .img-fluid. This applies
max-width: 100%; and height: auto; to the image so that it scales with the
parent width.
Image thumbnails
In addition to our border-radius utilities, you can use
.img-thumbnail to give an image a rounded 1px border appearance.
Aligning images
Align images with the helper float classes or
text alignment classes. block-level
images can be centered using
the .mx-auto margin utility class.
Picture
If you are using the <picture> element to specify multiple
<source> elements for a specific <img>, make sure to add the
.img-* classes to the <img> and not to the
<picture> tag.
<picture>
<source srcset="..." type="image/svg+xml" />
<img src="..." class="img-fluid img-thumbnail" alt="..." />
</picture>