I just want to ask what the Classic of Mountains and Seas in ancient books means.

There are many explanations, for example, geography refers to the line crossing the north and south poles at right angles to the equator, while Shan Hai Jing should refer to a monograph on something. Shan Hai Jing is an ancient book in the pre-Qin period in China, which mainly describes ancient myths, geography, products, witchcraft, religion, ancient history, medicine, folk customs and nationalities. The legend of Shan Hai Jing is well known, and the legendary hand tour of Xuanyuan is also well known in the game industry, recording ancient books.