v3.26.1
Stock-based compensation - Assumptions to determine grant-date fair value of stock options (Details) - Stock options
12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Stock-based Compensation    
Risk-free interest rate 3.97% 4.35%
Expected term (in years) 6 years 6 years
Expected volatility 77.20% 76.30%
Expected dividend yield 0.00% 0.00%