You might try: https://abookapart.com/ https://abookapart.com/ I read their _Responsive Web Design_ title a while back and found it helpful and concise. I see

You might try: https://abookapart.com/ https://abookapart.com/ I read their _Responsive Web Design_ title a while back and found it helpful and concise. I see there's a CSS3 title written by the founder of Dribbble, for example, and updated in 2015. This stuff changes so quickly, it may also be better to follow online, as others have suggested.