JavaFX - Resizable window using h- and v-boxes

resizable.fxml

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

<?import javafx.scene.control.Button?>
<?import javafx.scene.control.TextArea?>
<?import javafx.scene.layout.AnchorPane?>
<?import javafx.scene.layout.HBox?>
<?import javafx.scene.layout.VBox?>
<?import javafx.scene.text.Text?>

<VBox maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/15.0.1" xmlns:fx="http://javafx.com/fxml/1">
    <children>
        <HBox maxHeight="100.0" style="-fx-background-color: #224455;" VBox.vgrow="ALWAYS" />
        <HBox VBox.vgrow="ALWAYS">
            <children>
                  <HBox style="-fx-background-color: #001199;" HBox.hgrow="ALWAYS" />
                  <VBox maxWidth="450.0" HBox.hgrow="ALWAYS">
                      <children>
                          <VBox style="-fx-background-color: #111111;" VBox.vgrow="ALWAYS" />
                          <AnchorPane maxHeight="350.0" maxWidth="450.0" minHeight="350.0" minWidth="450.0" VBox.vgrow="ALWAYS">
                     <children>
                        <Button layoutX="199.0" layoutY="284.0" mnemonicParsing="false" text="Button" />
                        <TextArea layoutX="91.0" layoutY="69.0" prefHeight="195.0" prefWidth="269.0" />
                        <Text layoutX="214.0" layoutY="55.0" strokeType="OUTSIDE" strokeWidth="0.0" text="Text" />
                     </children>
                          </AnchorPane>
                          <VBox layoutX="10.0" layoutY="10.0" style="-fx-background-color: #111111;" VBox.vgrow="ALWAYS" />
                      </children>
                  </VBox>
                  <HBox style="-fx-background-color: #110099;" HBox.hgrow="ALWAYS" />
            </children></HBox>
        <HBox maxHeight="100.0" style="-fx-background-color: #112233;" VBox.vgrow="ALWAYS" />
    </children>
</VBox>