When comparing CSS-Tricks vs Can I use..., the Slant community recommends CSS-Tricks for most people. In the question“What are the best resources to learn CSS?” CSS-Tricks is ranked 2nd while Can I use... is ranked 12th. The most important reason people chose CSS-Tricks is:
All posts, whether they are written by Chris Coyier or a guest blogger, are very clear and well explained. Each example has code snippets with easy-to-follow explanations of the code and theory behind the specific concept. Possible issues you may run into with the code are often addressed, so you know how to tackle bugs that may pop up.
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Pros
Pro Examples are well explained
All posts, whether they are written by Chris Coyier or a guest blogger, are very clear and well explained. Each example has code snippets with easy-to-follow explanations of the code and theory behind the specific concept. Possible issues you may run into with the code are often addressed, so you know how to tackle bugs that may pop up.
Pro Codepen makes code review easy
Pro Frequently updated
CSS-Tricks is extremely active, being updated every day or two with a new blog post. Despite the frequency of the posts, the quality always remains high.
Pro Supplies usage data for all countries
Pro Provides good list of resources
When serching for a feature you typically find a nice list of really valuable resources, such as spec on w3c website, and blog posts desribing usage in details.
Cons
Con Not a good starting place for a complete beginner
CSS-Tricks does not follow the structure of a traditional tutorial, starting at the basics and gradually increasing in difficulty.
Instead, each blog post addresses a specific topic (such as responsive images, debugging keyframe animations etc.). Therefore it's better suited to someone who has already been introduced to CSS and is looking for more info on a specific topic, or wants to discover new concepts.
Con Not that good for learning
It's a super cool catalogue for people who know what they are doing, just to check if their tricks apply to certain use case or project. It doesn't serve as a good starting point nor roadmap for css newbies.