Images in Bootstrap 3 can be made responsive-friendly via the addition of the .img-responsive class. This applies max-width: 100%; and height: auto; to the image so that it scales nicely to the parent element.
<img src="..." class="img-responsive" alt="Responsive image">In Internet Explorer 8-10, SVG images with .img-responsive are disproportionately sized. To fix this, add width: 100% \9; where necessary. Bootstrap doesn't apply this automatically as it causes complications to other image formats.
Add classes to an <img> element to easily style images in any project.