设置javafx混合条形图/线形图样式的问题

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.chart.*;
import javafx.stage.Stage;

public class Main extends Application {

    @Override
    public void start(Stage primaryStage) {
        // 创建数据集
        XYChart.Series<String, Number> series1 = new XYChart.Series<>();
        series1.setName("Series 1");
        series1.getData().add(new XYChart.Data<>("Category 1", 10));
        series1.getData().add(new XYChart.Data<>("Category 2", 20));
        series1.getData().add(new XYChart.Data<>("Category 3", 30));

        XYChart.Series<String, Number> series2 = new XYChart.Series<>();
        series2.setName("Series 2");
        series2.getData().add(new XYChart.Data<>("Category 1", 15));
        series2.getData().add(new XYChart.Data<>("Category 2", 25));
        series2.getData().add(new XYChart.Data<>("Category 3", 35));

        // 创建混合条形图/线形图
        CategoryAxis xAxis = new CategoryAxis();
        NumberAxis yAxis = new NumberAxis();
        BarChart<String, Number> barChart = new BarChart<>(xAxis, yAxis);
        LineChart<String, Number> lineChart = new LineChart<>(xAxis, yAxis);

        // 添加数据集到图表
        barChart.getData().add(series1);
        lineChart.getData().add(series2);

        // 设置图表样式
        barChart.setStyle("-fx-background-color: #FFFFFF;");
        lineChart.setStyle("-fx-background-color: #FFFFFF;");

        // 设置轴标签和标题
        xAxis.setLabel("Category");
        yAxis.setLabel("Value");
        barChart.setTitle("Mixed Bar/Line Chart");

        // 创建场景并显示图表
        Scene scene = new Scene(barChart, 800, 600);
        primaryStage.setScene(scene);
        primaryStage.show();
    }

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