Note 3 - Stockholders' Equity - Warrant Activity (Details) - $ / shares |
6 Months Ended | 12 Months Ended |
|---|---|---|
Jun. 30, 2025 |
Dec. 31, 2024 |
|
| Warrants (in shares) | 5,694,445 | |
| Warrants, remaining contractual life (Year) | 4 years 6 months | 1 year 7 months 6 days |
| Warrants (in shares) | 1,250,000 | 5,694,445 |
| Minimum [Member] | ||
| Warrants, exercise price (in dollars per share) | $ 0.01 | |
| Warrants, exercise price (in dollars per share) | 0.01 | $ 0.01 |
| Maximum [Member] | ||
| Warrants, exercise price (in dollars per share) | 0.03 | |
| Warrants, exercise price (in dollars per share) | 0.03 | 0.03 |
| Weighted Average [Member] | ||
| Warrants, exercise price (in dollars per share) | 0.024 | |
| Warrants, exercise price (in dollars per share) | $ 0.014 | $ 0.024 |