v3.26.1
Share-based compensation - Schedule of Assumptions Used to Estimate Fair Values of Share Options Granted (Details) - ¥ / shares
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Share-based compensation      
Dividend yield 0.00% 0.00% 0.00%
Employee Stock Option      
Share-based compensation      
Risk-free interest rate, minimum 4.19% 3.88% 3.45%
Risk-free interest rate, maximum 4.24%    
Expected volatility, minimum 59.61% 57.25% 56.55%
Expected volatility, maximum 60.01%    
Weighted average expected volatility 59.83% 57.25% 56.55%
Minimum | Employee Stock Option      
Share-based compensation      
Expected exercise multiple ¥ 2.5 ¥ 2.5 ¥ 2.5
Maximum | Employee Stock Option      
Share-based compensation      
Expected exercise multiple ¥ 2.8 ¥ 2.8