Investment Income - Schedule of investment income (Details)	6 Months Ended
Jun. 30, 2026 HKD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 HKD ($)
Other Income and Expenses [Abstract]
Option premium income	$ 8,139,300	$ 1,037,911	$ 0
Realized gain on disposal of digital assets	214,867	27,400	0
Investment income from stable coins and digital assets	5,188,573	661,639	0
Change in fair value of derivative liabilities	2,158,422	275,239	0
Change in fair value of stable coins, digital assets and digital assets – restricted	(2,124,820,727)	(270,953,931)	0
Change in fair value of marketable securities	1,616,700	206,159	0
Others	(92,802)	(11,834)	0
Total investment gain (losses), net	$ (2,107,595,667)	$ (268,757,417)	$ 0

Crypto Asset, Investment Income, Nonoperating

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- Definition

Gain (Loss) On Investments, Including Changes In Fair Value Of Assets And Liabilities, Net

+ References

No definition available.

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- Definition

Amount of realized gain (loss) from remeasurement of crypto asset, classified as nonoperating. Excludes crypto asset held for platform user.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 60
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476163/350-60-45-2

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Amount of unrealized gain (loss) from remeasurement of crypto asset, classified as nonoperating. Excludes crypto asset held for platform user.

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
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-Publisher FASB
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Amount of realized and unrealized gain (loss) on investment.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

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- Definition

Amount of unrealized gain (loss) on investment in marketable security.

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