When it comes down to writing CSS there are lots of dangers and failures you may run into sooner or later. Some of them may occure out of poor naming conventions and confusing stylesheet structuring, others may be the cause of not knowing the right way to accomplish a desired solution.
The good news is: All of this headache can be avoided IF you know where to look for the right cheat sheets. This post is my attempt to create a list of recommendations of what sites you have to pay a good read, if you want to improve yourself as a CSS architect. And as a frontend developer in general of course.