Related party balances and transactions - Amounts due from related parties (Details) - CNY (¥)	Dec. 31, 2025	Dec. 31, 2024
Related party balances and transactions
Amounts due from related parties		¥ 4,439,705
Other Receivable, after Allowance for Credit Loss, Current, Related Party [Extensible Enumeration]	Related Party	Related Party
Mr. Yuan Li \| Related Party
Related party balances and transactions
Amounts due from related parties		¥ 4,439,705
Other Receivable, after Allowance for Credit Loss, Current, Related Party [Extensible Enumeration]		Related Party

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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