import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class Launcher extends Application {
    public static void main (String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage stage) {
        VBox root = new VBox();
        Scene scene = new Scene(root, 900, 600);
        scene.getStylesheets().add(getClass().getClassLoader().getResource("style.css").toExternalForm());
        stage.setScene(scene);
        ToolBarSeparator tbs = new ToolBarSeparator();
        Button button = new Button("Hello");
        root.getChildren().addAll(tbs, button);
        stage.show();
    }
}