Note 4 - Summary of Significant Accounting Policies - Exchange Rates Used to Translate Amounts in RMB into US (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Balance sheet items, except for equity accounts	7.1055		7.1055		7.1884
Items in the statements of operations and comprehensive loss	7.1292	7.1169	7.1642	7.1092