八千米深海十厘米蔚蓝
[bā qiān mĭ shēn hăi shí lí mĭ yù lán]
A beautiful and poetic description combining depth ('8000 meters deep sea') with beauty ('10 centimeters blue'). Imagines a contrast between the infinite depths below and an infinitely clear and beautiful ocean surface. It can also suggest the small but intense beauty amidst vast unknowns.