Long-term investments, net - Changes in investments accounted for using measurement alternative (Details) - CNY (¥) ¥ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Long-term investments, net
Balance at the beginning of the year	¥ 51,176	¥ 44,621
Additions		6,555
Disposals	(52,773)
Fair value re-measurement	142,556
Balance at the end of the year	140,959	¥ 51,176
Unrealized gains from re-measurement	¥ 101,400

Amount of investment in equity security without readily determinable fair value.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 321
-SubTopic 10
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-Publisher FASB
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Amount of unrealized gain (loss) on investment.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
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Amount of increase in equity securities without readily determinable fair value from addition.

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Amount of decrease in equity securities without readily determinable fair value from disposition.

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Amount of gain (loss) from remeasurement of fair value of equity investments accounted for using the measurement alternative.

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