v3.26.1
INCOME TAXES - Deferred tax assets and deferred tax liabilities (Details) - CNY (¥)
¥ in Thousands
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Deferred tax assets        
Net operating loss carry forwards ¥ 722,225 ¥ 712,079    
Deductible temporary differences 116,857 79,736    
Deferred revenue 24,412 15,283    
Less: valuation allowance (863,494) (807,098) ¥ (639,234) ¥ (410,857)
Net deferred tax assets ¥ 0 ¥ 0