阳光未必温暖凉薄未必情浅
[yáng guāng wèi bì wēn nuăn liáng bó wèi bì qíng qiăn]
'Sunny days don't necessarily mean warmth; indifference doesn't imply shallow affection.' It highlights that appearances aren't always reliable indicators: even in bright sunshine, one may not experience warmth or comfort; moreover, someone seemingly aloof or emotionally reserved could still deeply cherish another.