Chris Pennington is a US developer and founder of Tailwind Mastery, focused entirely on Tailwind CSS as a styling system. He is one of the more consistent independent voices on Tailwind beyond the official documentation, with paid course material on advanced Tailwind patterns.
His CourseFlix listing carries a Chris Pennington Tailwind CSS course. Material is paid and aimed at front-end developers using Tailwind seriously enough to want depth beyond the utility-class basics.