Note 7 - Share-based Compensation - Fair Value Assumptions (Details) - Share-Based Payment Arrangement, Option [Member] - $ / shares	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Expected dividend yield	0.00%	0.00%
SEED 2022 Share Incentive Plan [Member]
Expected dividend yield	0.00%	0.00%
Contractual life (years) (Year)		5 years
Minimum [Member]
Fair value of ordinary share (in dollars per share)	$ 1.34	$ 0.9
Risk-free interest rate	3.77%	3.84%
Expected term (years) (Year)	3 years	2 years 10 months 20 days
Expected volatility	105.00%	110.00%
Contractual life (years) (Year)	5 years	5 years
Minimum [Member] \| SEED 2022 Share Incentive Plan [Member]
Fair value of ordinary share (in dollars per share)	$ 1.46	$ 0.19
Risk-free interest rate	3.81%	3.51%
Expected term (years) (Year)	5 years 6 months	3 years 9 months
Expected volatility	114.02%	117.10%
Contractual life (years) (Year)		10 years
Maximum [Member]
Fair value of ordinary share (in dollars per share)		$ 3.6
Risk-free interest rate	4.03%	4.52%
Expected term (years) (Year)	5 years 6 months	6 years 3 months
Expected volatility	115.00%	140.00%
Contractual life (years) (Year)	10 years	10 years
Maximum [Member] \| SEED 2022 Share Incentive Plan [Member]
Fair value of ordinary share (in dollars per share)	$ 1.69	$ 1.46
Risk-free interest rate	4.44%	4.31%
Expected term (years) (Year)	10 years	6 years 3 months
Expected volatility	126.34%	141.40%
Contractual life (years) (Year)	10 years

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iv)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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