v3.26.1
Summary of significant accounting policies - Schedule of financial statement amounts and balances of the VIEs (Details)
 12 Months Ended
Dec. 31, 2025
CNY (¥)
Dec. 31, 2025
USD ($)
Dec. 31, 2024
CNY (¥)
Dec. 31, 2023
CNY (¥)
Dec. 31, 2025
USD ($)
ASSETS          
Cash and cash equivalents ¥ 1,759,126,853   ¥ 1,017,148,142 ¥ 4,440,131,180 $ 251,551,794
Restricted cash 34,931   83,387   4,995
Short-term bank deposits 502,501,754   3,070,374,400   71,856,795
Accounts receivable, net 77,583,990   49,056,771   11,094,363
Prepayments 15,790,383   26,884,785   2,257,995
Amounts due from related parties 91,600,802   74,174,692   13,098,740
Other current assets 185,264,173   231,353,868   26,492,424
Property and equipment, net 5,039,863   7,093,429   720,691
Long-term bank deposits     360,000,000    
Intangible assets, net 33,579,905   60,917,092   4,801,863
Right-of-use assets 7,900,307   15,816,035   1,129,729
Investments 383,683,224   456,814,694   54,865,971
Other non-current assets 57,844,845   76,615,919   8,271,704
TOTAL ASSETS 3,119,951,030   5,446,333,214   446,147,064
LIABILITIES          
Accounts payable 554,131,285   498,667,437   79,239,720
Advances from customers 2,311,403   4,443,895   330,526
Deferred revenue 236,899,790   252,346,104   33,876,219
Accrued expenses and other current liabilities 218,920,812   242,517,101   31,305,260
Amounts due to related parties 112,306,534   222,588,850   16,059,621
Lease liabilities 1,306,423   4,222,724   186,816
TOTAL LIABILITIES 1,132,579,100   1,236,243,988   $ 161,956,657
Income Statement          
Net revenues 3,818,851,679 $ 546,088,526 4,270,825,456 5,530,404,557  
Net (loss) income (29,081,925) (4,158,660) (306,810,286) 35,517,634  
Statement of Cash Flows          
Net cash (used in) provided by operating activities (52,254,816) (7,472,339) (238,851,936) (47,687,219)  
Net cash provided by investing activities 2,971,800,293 424,961,790 (1,074,492,728) 414,184,628  
Net cash used in financing activities (2,150,781,250) $ (307,557,628) (2,206,974,529) (965)  
Consolidated VIEs          
ASSETS          
Cash and cash equivalents 469,616,029   339,495,145    
Restricted cash 34,931   83,387    
Short-term bank deposits 196,493,754   80,000,000    
Accounts receivable, net 76,835,525   48,706,963    
Prepayments 15,565,395   26,353,088    
Amounts due from related parties 91,548,882   74,116,192    
Other current assets 169,919,175   175,835,175    
Property and equipment, net 2,626,675   3,088,802    
Long-term bank deposits     160,000,000    
Intangible assets, net 32,278,768   59,542,225    
Right-of-use assets 3,341,437   12,891,088    
Investments 195,447,619   193,677,231    
Other non-current assets 56,286,173   63,013,382    
TOTAL ASSETS 1,309,994,363   1,236,802,678    
LIABILITIES          
Accounts payable 498,282,741   436,642,460    
Advances from customers 2,277,588   4,412,848    
Deferred revenue 236,124,062   251,591,800    
Accrued expenses and other current liabilities 111,867,960   117,124,157    
Amounts due to related parties 111,302,560   220,194,409    
Lease liabilities 3,165,386   12,649,480    
TOTAL LIABILITIES 963,020,297   1,042,615,154    
Income Statement          
Net revenues 3,809,355,931   4,234,608,729 5,459,630,803  
Net (loss) income 185,239,077   (266,581,526) (49,971,489)  
Statement of Cash Flows          
Net cash (used in) provided by operating activities 85,673,058   (385,060,569) (180,359,213)  
Net cash provided by investing activities ¥ 47,771,310   ¥ 380,148,093 55,516,731  
Net cash used in financing activities       ¥ (965)