Subsequent events	12 Months Ended
Dec. 31, 2025
Subsequent events
Subsequent events	18.Subsequent events The Company has evaluated subsequent events through the issuance of the consolidated financial statements and concluded that no subsequent events have occurred that would require recognition or disclosure in the consolidated financial statements other than as disclosed below. On February 9, 2026, the Company established Beijing YJZY Tech Co., Ltd. in PRC. In April 2026, a wholly-owned subsidiary of the Company borrowed RMB1,100 (approximately US$157) from a third party for daily operation. The loan has an annual interest of 6% and a one-year maturity.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

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