Seems like a largely semantic debate about the definition of "logical" is taking place in the comments here. CSS is logical in that it follows a set of rules, but that is the case for every computer program by definition, so it's not informative or useful. People claiming that CSS is not logical probably mean that it's poorly designed and not easily understood by humans, which is probably a question of taste more than anything objectively measurable, though I happen to agree.
I just think it's more a question of the mental model that is in your head. Learning languages is the same. A language can have a syntactical/linguistic feature that seems very strange when you have the mental model of your own native language in mind, but the more practice the new model the more it begins to "make sense" until - voila - you get it.
Normal mode in VIM is an another example. The first time I experienced it, it seemed absolutely bizarre.
I think a good way to think about good design is the Einstein quote on mathematical models, that they should be "...as simple as possible, but no simpler." Normal mode in vi/vim is necessary for that program's goal of keeping your fingers on the center of the keyboard as much as possible: forgoing the use of arrow keys means that navigation and editing have to be separate modes. It's more complex, but only because it has to be. CSS on the other hand seems to introduce a whole lot of accidental, unnecessary complexity.
