I use a mixture of underscores and dashes. I agree with Paulie for the modular use. I then throw in an “_” when the variable is multiple words. E.g. “btn-class_name”. Although it seems overly complicated, I do I for the simple reason that when you double click it, it selects the entire “class_name” and ignores anything separated by a “-“. I think the camelCase that you prefer also does that well.