JavaFX Design - Modern Login Screen

color.css

/*Color gradient*/
.colorBackground{
    -fx-background-color: linear-gradient( to right top,#facd68, #fc76b3);
}

Controller.java

package sample;

import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.layout.AnchorPane;
import javafx.stage.Stage;

import java.net.URL;
import java.util.ResourceBundle;

public class Controller implements Initializable {

    private double x = 0,y = 0;

    @FXML
    private AnchorPane sideBar;

    private Stage stage;

    @Override
    public void initialize(URL url, ResourceBundle resourceBundle) {
        sideBar.setOnMousePressed(mouseEvent -> {
            x = mouseEvent.getSceneX();
            y = mouseEvent.getSceneY();
        });

        sideBar.setOnMouseDragged(mouseEvent -> {
            stage.setX(mouseEvent.getScreenX() - x);
            stage.setY(mouseEvent.getScreenY() - y);
        });
    }

    public void setStage(Stage stage){
        this.stage = stage;
    }

    @FXML
    void closeProgram(ActionEvent event) {
        stage.close();
    }
}

Main.java

package sample;

import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.paint.Color;
import javafx.stage.Stage;
import javafx.stage.StageStyle;

public class Main extends Application {

    @Override
    public void start(Stage primaryStage) throws Exception{

        FXMLLoader loader = new FXMLLoader(getClass().getResource("sample.fxml"));
        Parent root = loader.load();
        Controller controller = loader.getController();
        Scene scene = new Scene(root);

        scene.setFill(Color.TRANSPARENT);
        primaryStage.initStyle(StageStyle.TRANSPARENT);

        primaryStage.setScene(scene);

        controller.setStage(primaryStage);
        primaryStage.show();
    }


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

sample.fxml

<?xml version="1.0" encoding="UTF-8"?>

<?import com.jfoenix.controls.JFXButton?>
<?import com.jfoenix.controls.JFXTextField?>
<?import javafx.scene.layout.AnchorPane?>
<?import javafx.scene.paint.Color?>
<?import javafx.scene.paint.LinearGradient?>
<?import javafx.scene.paint.Stop?>

<AnchorPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="600.0" style="-fx-background-color: transparent;" xmlns="http://javafx.com/javafx/15.0.1" xmlns:fx="http://javafx.com/fxml/1" fx:controller="sample.Controller">
   <children>
      <AnchorPane layoutX="224.0" layoutY="76.0" prefHeight="249.0" prefWidth="310.0" style="-fx-background-radius: 25; -fx-background-color: white;">
         <children>
            <JFXTextField layoutX="72.0" layoutY="53.0" prefHeight="25.0" prefWidth="174.0" promptText="Enter Login">
               <focusColor>
                  <LinearGradient endX="1.0" endY="1.0">
                     <stops>
                        <Stop>
                           <color>
                              <Color red="0.9803921580314636" green="0.8039215803146362" blue="0.40784314274787903" />
                           </color>
                        </Stop>
                        <Stop offset="1.0">
                           <color>
                              <Color red="0.9882352948188782" green="0.4627451002597809" blue="0.7019608020782471" />
                           </color>
                        </Stop>
                     </stops>
                  </LinearGradient>
               </focusColor>
            </JFXTextField>
            <JFXTextField layoutX="72.0" layoutY="109.0" prefHeight="25.0" prefWidth="174.0" promptText="Enter Password">
               <focusColor>
                  <LinearGradient endX="1.0" endY="1.0">
                     <stops>
                        <Stop>
                           <color>
                              <Color red="0.9803921580314636" green="0.8039215803146362" blue="0.40784314274787903" />
                           </color>
                        </Stop>
                        <Stop offset="1.0">
                           <color>
                              <Color red="0.9882352948188782" green="0.4627451002597809" blue="0.7019608020782471" />
                           </color>
                        </Stop>
                     </stops>
                  </LinearGradient>
               </focusColor>
            </JFXTextField>
            <JFXButton buttonType="RAISED" layoutX="112.0" layoutY="176.0" prefHeight="41.0" prefWidth="87.0" styleClass="colorBackground" stylesheets="@color.css" text="Login" />
         </children>
      </AnchorPane>
      <AnchorPane fx:id="sideBar" layoutX="31.0" layoutY="53.0" prefHeight="295.0" prefWidth="220.0" style="-fx-background-radius: 25;" styleClass="colorBackground" stylesheets="@color.css">
         <children>
            <JFXButton layoutX="182.0" layoutY="14.0" onAction="#closeProgram" text="X" />
         </children>
      </AnchorPane>
   </children>
</AnchorPane>