This course explores the customization of Bootstrap 5, the latest iteration of the most popular CSS framework for developing responsive and mobile-first websites. It emphasizes how Bootstrap 5 has been improved with a new API, enhanced grid system, and utility classes that enable more fine-grained control over layouts and designs. The course guides participants through the process of tailoring Bootstrap’s pre-built components and layout utilities to meet specific design requirements without sacrificing the mobile-first philosophy. Learners are taught how to modify the Sass variables, utilize the custom CSS classes, and leverage Bootstrap’s extensive theming capabilities to create a unique look and feel while maintaining accessibility and responsiveness. The course also discusses the use of Bootstrap’s JavaScript plugins to extend functionality and enhance user interactivity. By the end, participants understand how to make Bootstrap 5 fit any design aesthetic while keeping the robustness and simplicity of the framework intact.