v3.26.1
Summary of significant accounting policies - Additional information (Details)
1 Months Ended 12 Months Ended
Jan. 31, 2024
CNY (¥)
Dec. 31, 2025
CNY (¥)
segment
$ / ¥
Dec. 31, 2024
CNY (¥)
Dec. 31, 2023
CNY (¥)
Dec. 31, 2025
USD ($)
$ / ¥
Summary of significant accounting policies          
Service fees charged   ¥ 149,512,987 ¥ 198,006,640 ¥ 354,509,123  
Due to WFOE   ¥ 1,748,790,690 ¥ 1,691,181,872    
Percentage Of VIE contribution to consolidated revenue   99.00% 99.00% 99.00% 99.00%
Percentage Of VIE accounted of consolidated total assets   42.00% 23.00%   42.00%
Percentage Of VIE accounted of consolidated total liabilities   85.00% 84.00%   85.00%
Convenience translation rate per US$1.00 | $ / ¥   6.9931     6.9931
Impairment loss of investments   ¥ 0 ¥ 7,085,156 ¥ 29,123,511  
Fair value changes on investments   (65,200,488) 40,628,028 0  
Deferred revenue ¥ 251,591,800        
Capitalized research and development expenses   ¥ 0 0 0  
Number of operating segments | segment   1      
Number of reportable segment | segment   1      
Government subsidies   ¥ 2,287,338 5,234,088 29,733,380  
Cash and cash equivalents   1,759,126,853 1,017,148,142 4,440,131,180 $ 251,551,794
CHINA          
Summary of significant accounting policies          
Cash and cash equivalents   ¥ 486,342,603      
Cash and cash equivalents percentage   28.00%     28.00%
Other expenses, net          
Summary of significant accounting policies          
Group recorded impairment loss other (expenses) income   ¥ 2,114,370 ¥ 19,689,373 ¥ 58,005,769