Whether you are a beginner, or experienced developer who needs a CSS refresher, Modern CSS is the book for you. Joe Attardi, my former colleague has done an excellent job teaching every concept accompanied by code examples and screenshots
This is a full CSS (Cascading Style Sheet) course for beginners to learn everything from basic to highly advanced skills.
This article goes some way towards demystifying exmplicit versus explicit tracks when working with CSS Grid and equips you with some valuable knowledge to help you debug broken layouts. Here is the link: https://css-irl.info/debugging-css-grid-part-1-understanding-implicit-tracks/