What are the characteristics of "sunset" and "cicada" in China's classical poems?

Sunset is often used by ancient literati to describe the scenery, either spectacular or fresh, but there is a sadness, which is the common intention of some incompetent and unscrupulous literati who serve the country.

Cicada is often used as a metaphor for noble character in ancient poems. Among them, Luo's Wang Binyong is the most famous.