private static IllegalArgumentException newInvalidColorException( String value ) {
		return new IllegalArgumentException( "invalid color '" + value + "'" );
	}
Parses a hex color in  {@code #RGB}, {@code #RGBA}, {@code #RRGGBB} or {@code #RRGGBBAA}
format and returns it as {@code rgba} integer suitable for {@link java.awt.Color},
which includes alpha component in bits 24-31.
flatlaf-core/src/main/java/com/formdev/flatlaf/UIDefaultsLoader.java