private void resize() {
        mainMenuButton.relocate((getPrefWidth() - options.getButtonSize()) * 0.5, (getPrefHeight() - options.getButtonSize()) * 0.5);
        for (Parent node : items.keySet()) {
            node.setLayoutX((getPrefWidth() - node.getLayoutBounds().getWidth()) * 0.5);
            node.setLayoutY((getPrefHeight() - node.getLayoutBounds().getHeight()) * 0.5);
        }
    }