diff --git a/build.gradle b/build.gradle
index 5ed3b31..0d565c6 100644
--- a/build.gradle
+++ b/build.gradle
@@ -9,7 +9,7 @@ compileJava.options.encoding = 'UTF-8'
 
 project.ext.junitVersion = '5.3.1'
 
-mainClassName = '_9.HelloWorld'
+mainClassName = '_9._1.ColorMixer'
 
 sourceCompatibility = 1.8
 
diff --git a/src/main/java/_9/_1/ColorMixer.java b/src/main/java/_9/_1/ColorMixer.java
new file mode 100644
index 0000000..470c351
--- /dev/null
+++ b/src/main/java/_9/_1/ColorMixer.java
@@ -0,0 +1,50 @@
+package _9._1;
+
+import javafx.application.Application;
+import javafx.geometry.Insets;
+import javafx.geometry.Pos;
+import javafx.scene.Scene;
+import javafx.scene.control.Slider;
+import javafx.scene.layout.*;
+import javafx.scene.paint.Color;
+import javafx.scene.paint.Paint;
+import javafx.scene.shape.Rectangle;
+import javafx.stage.Stage;
+
+public class ColorMixer extends Application {
+
+	@Override
+	public void start(Stage stage) {
+		VBox vBox = new VBox(10);
+		vBox.setAlignment(Pos.TOP_CENTER);
+		vBox.setPadding(new Insets(10));
+
+		Rectangle rectangle = new Rectangle(200, 200);
+
+		Slider red = colorSlider(Color.RED);
+		Slider green = colorSlider(Color.GREEN);
+		Slider blue = colorSlider(Color.BLUE);
+		red.valueProperty().addListener((observable, oldValue, newValue) -> rectangle.setFill(Color.rgb(newValue.intValue(), (int) green.getValue(), (int) blue.getValue())));
+		green.valueProperty().addListener((observable, oldValue, newValue) -> rectangle.setFill(Color.rgb((int) red.getValue(), newValue.intValue(), (int) blue.getValue())));
+		blue.valueProperty().addListener((observable, oldValue, newValue) -> rectangle.setFill(Color.rgb((int) red.getValue(), (int) green.getValue(), newValue.intValue())));
+
+		vBox.getChildren().addAll(rectangle, red, green, blue);
+		Scene scene = new Scene(new StackPane(vBox), 600, 360);
+		stage.setScene(scene);
+		stage.setTitle("Color-Mixer");
+		stage.setResizable(false);
+		stage.show();
+	}
+
+	private Slider colorSlider(Paint fill) {
+		Slider slider = new Slider(0, 255, 0);
+		slider.setShowTickLabels(true);
+		slider.setShowTickMarks(true);
+		slider.setBackground(new Background(new BackgroundFill(fill, CornerRadii.EMPTY, Insets.EMPTY)));
+		return slider;
+	}
+
+	public static void main(String[] args) {
+		launch();
+	}
+}
\ No newline at end of file