v3.26.3
Summary of significant accounting policies (Tables)
6 Months Ended
Jun. 30, 2026
Summary of significant accounting policies  
Summary of estimated useful lives of property and equipment

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Useful life

Motor vehicles

 

4 years

Office equipment

 

3 years

Leasehold improvement

 

Over shorter of the lease term and the remaining useful life

Schedule of useful lives using the straight-line method,

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Useful life

Software

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5 to 10 years

Copyrights

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10 years

Schedule of disaggregates revenue

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For the six months ended June 30,

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2025

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2026

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2026

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RMB

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RMB

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US$

Revenue by services line

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Adult education supporting services

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5,671,628

 

5,074,720

 

747,921

Safety technology training services

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3,503,890

 

2,290,080

 

337,516

Online course services

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208,072

 

66,081

 

9,740

Customized equipment

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—

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843,337

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124,292

Total revenue

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9,383,590

 

8,274,218

 

1,219,469

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For the six months ended June 30,

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2025

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2026

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2026

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RMB

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RMB

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US$

Revenue by recognition method

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Revenue recognized over time

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9,175,518

 

8,208,137

 

1,209,729

Revenue recognized at a point in time

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208,072

 

66,081

 

9,740

Total revenue

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9,383,590

 

8,274,218

 

1,219,469