白天不懂夜的黑蓝天不懂海的伤
[bái tiān bù dŏng yè de hēi lán tiān bù dŏng hăi de shāng]
"Day Fails To Understand The Night’s Darkness And Blue Sky Cannot Grasp The Sea’s Wounds." This metaphor compares day and night to blue sky and the sea. Here, 'night’ and 'sea' are seen as profound and sorrowful, which the 'day’ and ‘sky’—metaphors for outsiders or the ignorant—cannot truly appreciate.