Bootstrap is the most popular framework for building responsive, mobile-first websites. When you combine it with Sass, you get CSS superpowers and a level of customization that makes Bootstrap even more powerful. This course explores the differences between regular Bootstrap and the new Sass-driven version, Bootstrap 4, and shows how to use the Sass-enabled features to build more customized sites. Instructor Ray Villalobos shows how to install libraries to add custom fonts, icons, and animations; use Sass variables, maps, and mixins to create custom layouts; modify global settings; and customize existing components with CSS and Sass.