Once you're familiar with the basics of CSS, you're ready to expand your skillset and tackle more challenging concepts. In this course—the second installment in a series—bolster your existing CSS knowledge, and learn advanced concepts that can help you write more efficient code. Join Christina Truong as she explains how to work with a variety of advanced selectors, when to use the float, display, and position properties, and how to get started with the CSS browser developer tools and leverage them when debugging your front-end code. She also explains how to take a mobile-first approach to responsive web design. Plus, this course provides you with an opportunity to add more features to the online résumé project you started in CSS Essential Training 1.