v3.26.1
Accounts receivable, net - Schedule of credit loss provision (Details)
12 Months Ended
Dec. 31, 2025
CNY (¥)
Dec. 31, 2025
USD ($)
Dec. 31, 2024
CNY (¥)
Dec. 31, 2023
CNY (¥)
Accounts receivable, net        
Balance as of January 1 ¥ 17,725,683   ¥ 20,164,070 ¥ 8,875,133
Addition (Reversal) (2,909,475) $ (416,049) (1,944,636) 11,809,161
Write offs     (493,751) (520,224)
Balance as of December 31 ¥ 14,816,208   ¥ 17,725,683 ¥ 20,164,070