Hey everyone!

Just a quick question about key signatures! [br][br]I am at the end of guitar fundamentals two and I am feeling pretty confident with key signatures etc and barre chords and the Magic L etc. [br][br]However, I am slighyl confused today I was playing a barre chord progression of A major C major and d major. If this is in the Key of A surely c major would sound off in this sequence but it doesnt it fits perfectly. Can anyone advise or am I taking the Magic L too seriously?[br][br]Kind Regards

Tim