Does 青天 really mean "a sunny blue sky"? Some dictionaries define it as "碧蓝的天空", but the 例句s seem to be describing a cloudless night sky. For instance, 李白: 欲上青天揽明月; 青天有月来几时; 牛渚西江夜，青天无片云. 李商隐: 嫦娥应悔偷灵药，碧海青天夜夜心. 苏轼: 明月几时有? 把酒问青天. 黄庭坚: 今夕清辉不足? 万里青天，姮娥何处. 韩愈: 漠漠轻阴晚自开，青天白日映楼台 (薄薄的阴云在傍晚时分消失了...白日 refers to 落日 as in 白日依山尽 "太阳西沉，就要落山了") Even the famous 包青天 is known for his dark skin, dark as night. So, what does 青天 actually mean?