There is a single flag matching these criteria: Flag of Kansas.
Orange in Flags
Orange is less common in flag design but carries strong cultural meaning where it is used. It often represents courage, sacrifice, or the sun. In Ireland, orange signifies the Protestant community, while in India it symbolizes courage and sacrifice as part of the saffron band. The Netherlands historically associated orange with the royal House of Orange. Flags with orange stand out for their vibrant and energetic appearance.
Yellow in Flags
Yellow (or gold) is frequently linked to wealth, prosperity, and the sun. It represents energy, optimism, and generosity. Many flags incorporate yellow to highlight natural resources or national wealth, such as Spain, Germany, and Brazil. In some cases, yellow has a religious meaning, symbolizing divinity or enlightenment. Its brightness makes it a striking choice in flag design, often paired with darker colors for contrast.
Purple in Flags
Purple is rare in flags due to the historical cost of purple dye, but where it appears, it symbolizes royalty, wealth, and spirituality. The color’s association with nobility made it prestigious, though few countries use it today. Modern examples include the flag of Dominica and the flag of Nicaragua, which both feature purple elements. Because of its rarity, purple stands out as a symbol of uniqueness and distinction.