Ancient poetry is a model of classical Chinese, with diverse themes.
For example: Poetry and Qufu, ancient poetry is a genre of classical Chinese.
"Classical Chinese" is relative to "vernacular Chinese"
What is "classical Chinese"?
"Wen" refers to a written article.
"Speech" means writing, expressing and recording.
"Classical Chinese", that is, written language, is relative to "spoken language", which is also called "vernacular".
The last word "Wen" refers to works, articles, etc. , which means genre.
"Classical Chinese" means "articles written in written language". And "vernacular" means: "articles written in plain spoken language".
In ancient China, it was different to express the same thing in spoken and written language. For example, if you want to ask someone if they have eaten, you can express it in spoken English as "Have you eaten?" And using books and language to express it is "rice?" . "Fanbu" is classical Chinese. In ancient China, all articles were written in written language. Therefore, now we generally refer to ancient Chinese as "classical Chinese"