v3.26.1
Property, plant and equipment - Reconciliation of changes in property, plant and equipment (Details) - HKD ($)
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Disclosure of detailed information about property, plant and equipment [line items]    
Property, plant and equipment at beginning of period $ 2,059,621  
Depreciation of property, plant and equipment 1,198,520 $ 1,671,269
Property, plant and equipment at end of period 4,232,077 2,059,621
Leasehold improvements    
Disclosure of detailed information about property, plant and equipment [line items]    
Property, plant and equipment at beginning of period 927,512  
Property, plant and equipment at end of period 638,668 927,512
Factory and factory equipment    
Disclosure of detailed information about property, plant and equipment [line items]    
Property, plant and equipment at beginning of period 1,054,115  
Property, plant and equipment at end of period $ 1,375,124 1,054,115
Depreciation rate, property, plant and equipment 20.00%  
Lab equipment    
Disclosure of detailed information about property, plant and equipment [line items]    
Property, plant and equipment at beginning of period $ 77,994  
Property, plant and equipment at end of period $ 2,218,285 77,994
Depreciation rate, property, plant and equipment 33.00%  
Cost    
Disclosure of detailed information about property, plant and equipment [line items]    
Property, plant and equipment at beginning of period $ 3,922,705 3,641,185
Additions 3,237,154 606,296
Disposal 840,398 205,488
Exchange adjustments 220,346 (119,288)
Property, plant and equipment at end of period 6,539,807 3,922,705
Cost | Leasehold improvements    
Disclosure of detailed information about property, plant and equipment [line items]    
Property, plant and equipment at beginning of period 1,707,918 1,765,777
Additions 466,834 0
Disposal 0 0
Exchange adjustments 82,726 (57,859)
Property, plant and equipment at end of period 2,257,478 1,707,918
Cost | Factory and factory equipment    
Disclosure of detailed information about property, plant and equipment [line items]    
Property, plant and equipment at beginning of period 1,234,146 944,682
Additions 560,481 525,889
Disposal 0 205,488
Exchange adjustments 65,045 (30,937)
Property, plant and equipment at end of period 1,859,672 1,234,146
Cost | Lab equipment    
Disclosure of detailed information about property, plant and equipment [line items]    
Property, plant and equipment at beginning of period 980,641 930,726
Additions 2,209,839 80,407
Disposal 840,398 0
Exchange adjustments 72,575 (30,492)
Property, plant and equipment at end of period 2,422,657 980,641
Amortization    
Disclosure of detailed information about property, plant and equipment [line items]    
Property, plant and equipment at beginning of period (1,863,084) (244,253)
Depreciation of property, plant and equipment 1,198,520 1,671,269
Disposal (840,398) (44,522)
Exchange adjustments 86,524 (7,916)
Property, plant and equipment at end of period (2,307,730) (1,863,084)
Amortization | Leasehold improvements    
Disclosure of detailed information about property, plant and equipment [line items]    
Property, plant and equipment at beginning of period (780,406) (161,057)
Depreciation of property, plant and equipment 787,062 624,593
Disposal 0 0
Exchange adjustments 51,342 (5,244)
Property, plant and equipment at end of period (1,618,810) (780,406)
Amortization | Factory and factory equipment    
Disclosure of detailed information about property, plant and equipment [line items]    
Property, plant and equipment at beginning of period (180,031) (31,489)
Depreciation of property, plant and equipment 290,111 194,088
Disposal 0 (44,522)
Exchange adjustments 14,406 (1,024)
Property, plant and equipment at end of period (484,548) (180,031)
Amortization | Lab equipment    
Disclosure of detailed information about property, plant and equipment [line items]    
Property, plant and equipment at beginning of period (902,647) (51,707)
Depreciation of property, plant and equipment 121,347 852,588
Disposal (840,398) 0
Exchange adjustments 20,776 (1,648)
Property, plant and equipment at end of period $ (204,372) $ (902,647)