Using JAVAFX To build a ugly ball

import javafx.application.Application;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.paint.Color;
import javafx.scene.paint.CycleMethod;
import javafx.scene.paint.RadialGradient;
import javafx.scene.paint.Stop;
import javafx.scene.shape.Circle;
import javafx.stage.Stage;

public class Main extends Application {
    static int dx = 1;
    static int dy = 1;

    public static void main(String[] args) {
        Application.launch(args);
    }

    @Override
    public void start(final Stage primaryStage) {
        primaryStage.setTitle("Animation");
        Group root = new Group();
        Scene scene = new Scene(root, 400, 300, Color.WHITE);

        primaryStage.setScene(scene);
        addBouncyBall(scene); 
        primaryStage.show();
    }
    private void addBouncyBall(final Scene scene) {
        final Circle ball = new Circle(100, 100, 20);

        RadialGradient gradient1 = new RadialGradient(0,
            .1,
            100,
            100,
            20,
            false,
            CycleMethod.NO_CYCLE,
            new Stop(0, Color.YELLOW),
            new Stop(1, Color.BLACK));

        ball.setFill(gradient1);

    
        final Group root = (Group) scene.getRoot();
        root.getChildren().add(ball);

    }
}

this ball is so ugly, maybe you can change the color's position not putting in the middle.