Inventories (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
Mar. 31, 2025 CNY (¥)	Mar. 31, 2025 USD ($)	Mar. 31, 2024 CNY (¥)	Mar. 31, 2023 CNY (¥)
Inventories [Abstract]
Provision/(reversal) of inventory reserves	¥ 154	$ 21	¥ (223)	¥ 35

Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 330
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483080/330-10-50-2

Name:	us-gaap_InventoryWriteDown
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration