v3.26.1
Summary of significant accounting policies (Details 3)
6 Months Ended
Jun. 30, 2026
USD ($)
Jun. 30, 2026
CNY (¥)
Jun. 30, 2025
CNY (¥)
Total revenues $ 20,071,752 ¥ 136,706,698 ¥ 188,112,127
Mainland PRC [Member]      
Total revenues 10,903,118 74,260,052 142,800,304
Hong Kong Revenues [Member]      
Total revenues $ 9,168,634 ¥ 62,446,646 ¥ 45,311,823