Other current assets - Allowance for other current assets (Details) |
12 Months Ended | ||
|---|---|---|---|
|
Dec. 31, 2025
CNY (¥)
|
Dec. 31, 2025
USD ($)
|
Dec. 31, 2024
CNY (¥)
|
|
| Other current assets | |||
| Balance at the beginning of the year | ¥ 72,671,045 | $ 10,391,821 | ¥ 116,860,992 |
| Additions/(reversal) | 5,587,076 | 798,941 | (15,572,138) |
| Charge-offs | (764,195) | (109,278) | (28,617,809) |
| Balance at the end of the year | ¥ 77,493,926 | $ 11,081,484 | ¥ 72,671,045 |