Use external css in JavaFX for styling

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.PasswordField;
import javafx.scene.control.TextField;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Color;
import javafx.scene.text.Font;
import javafx.scene.text.FontWeight;
import javafx.scene.text.Text;
import javafx.stage.Stage;

/**
 *
 * @author kundan
 */
public class JavaFxTest extends Application {
    
    @Override
    public void start(Stage primaryStage) {       
        primaryStage.setTitle("JavaFX Welcome");
        GridPane grid = new GridPane();
        grid.setAlignment(Pos.CENTER);
        grid.setHgap(10);
        grid.setVgap(10);
        grid.setPadding(new Insets(25, 25, 25, 25));
        Text scenetitle = new Text("Welcome");
        scenetitle.setFont(Font.font("Tahoma", FontWeight.NORMAL, 20));
        scenetitle.setId("welcome-text");
        grid.add(scenetitle, 0, 0, 2, 1);

        Label userName = new Label("User Name:");
        userName.setMinSize(80, 50);
        grid.add(userName, 0, 1);

        TextField userTextField = new TextField();
        grid.add(userTextField, 1, 1);

        Label pw = new Label("Password:");
        pw.setMinSize(80, 50);
        grid.add(pw, 0, 2);

        PasswordField pwBox = new PasswordField();
        grid.add(pwBox, 1, 2);
        Button btn = new Button("Sign in");
        HBox hbBtn = new HBox(10);
        hbBtn.setAlignment(Pos.BOTTOM_RIGHT);
        hbBtn.getChildren().add(btn);
        grid.add(hbBtn, 1, 4);
        final Text actiontarget = new Text();
        grid.add(actiontarget, 1, 6);
        btn.setOnAction(new EventHandler() {
 
    @Override
    public void handle(ActionEvent e) {
        actiontarget.setFill(Color.FIREBRICK);
        actiontarget.setText("Sign in button pressed");
    }
    });
        Scene scene = new Scene(grid, 300, 275);
        scene.getStylesheets().add
 (JavaFxTest.class.getResource("Login.css").toExternalForm());
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        launch(args);
    }
}

.root {
     -fx-background-image: url("background.jpg");
}
.label {
    -fx-font-size: 12px;
    -fx-font-weight: bold;
    -fx-text-fill: #333333;
    -fx-effect: dropshadow( gaussian , rgba(255,255,255,0.5) , 0,0,0,1 );
}
#welcome-text {
   -fx-font-size: 32px;
   -fx-font-family: "Arial Black";
   -fx-fill: #818181;
   -fx-effect: innershadow( three-pass-box , rgba(0,0,0,0.7) , 6, 0.0 , 0 , 2 );
}
#actiontarget {
  -fx-fill: FIREBRICK;
  -fx-font-weight: bold;
  -fx-effect: dropshadow( gaussian , rgba(255,255,255,0.5) , 0,0,0,1 );  
}