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Images
Responsive Images
Images are made responsive with .img-fluid. This applies max-width: 100%; and height: auto; to the image so that it scales with the parent element.
<img src="..." class="img-fluid" alt="...">Image thumbnails
In addition to our border-radius utilities, you can use .img-thumbnail to give an image a rounded 1px border appearance.
<img src="..." class="img-thumbnail" alt="...">