To customize default bootstrap components and variables use stylesheets/bs.scss

You can use all the available components of TwitterBootstrap. Here are some of them.

Buttons and Font Awesome

It imports the latest version of Font Awesome. You can use it with buttons like so:

<button type="button" class="btn btn-primary"> Tweet</button> <button type="button" class="btn btn-default"> Email</button>

Text Helpers

Modify text with text helper classes. Documentations here and here.

Use text-muted to mute text color.

Use lead to for call-out text.

Use text-center to center text.

Alerts

Responsive Embed

Add embed-responsive and either embed-responsive-16by9 or embed-responsive-4by3 classes to make embedded objects responsive.

JavaScript Components

You can use all of the JavaScript components included by Bootstrap. Example: A modal dialog.

Customizing Bootstrap

Autm-rb uses bootstrap-sass, so all of the variables are customizable.