diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 40ca0af..3b49093 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -11,11 +11,8 @@
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
         android:theme="@style/Theme.AndroidFundamentalsMai2021">
-        <activity android:name=".ConstraintLayoutSampleActivity"></activity>
-        <activity android:name=".MainActivity" />
-        <activity android:name=".EmailsActivity" />
-        <activity android:name=".StartActivity">
-            <intent-filter>
+        <activity android:name=".Course4CodeChallenge3">
+           <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 
                 <category android:name="android.intent.category.LAUNCHER" />
diff --git a/app/src/main/java/com/magdamiu/androidfundamentalsmai2021/Course4CodeChallenge3.java b/app/src/main/java/com/magdamiu/androidfundamentalsmai2021/Course4CodeChallenge3.java
new file mode 100644
index 0000000..cc0e781
--- /dev/null
+++ b/app/src/main/java/com/magdamiu/androidfundamentalsmai2021/Course4CodeChallenge3.java
@@ -0,0 +1,14 @@
+package com.magdamiu.androidfundamentalsmai2021;
+
+import androidx.appcompat.app.AppCompatActivity;
+
+import android.os.Bundle;
+
+public class Course4CodeChallenge3 extends AppCompatActivity {
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_course4_code_challenge3);
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/res/drawable/header_image.jpg b/app/src/main/res/drawable/header_image.jpg
new file mode 100644
index 0000000..4abb4c8
Binary files /dev/null and b/app/src/main/res/drawable/header_image.jpg differ
diff --git a/app/src/main/res/drawable/poster_sparkling.jpg b/app/src/main/res/drawable/poster_sparkling.jpg
new file mode 100644
index 0000000..5971677
Binary files /dev/null and b/app/src/main/res/drawable/poster_sparkling.jpg differ
diff --git a/app/src/main/res/layout/activity_course4_code_challenge3.xml b/app/src/main/res/layout/activity_course4_code_challenge3.xml
new file mode 100644
index 0000000..87615f9
--- /dev/null
+++ b/app/src/main/res/layout/activity_course4_code_challenge3.xml
@@ -0,0 +1,114 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".Course4CodeChallenge3">
+
+    <ImageView
+        android:id="@+id/header_image"
+        android:layout_width="wrap_content"
+        android:layout_height="@dimen/space_272"
+        android:contentDescription="@string/header_imagine"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent"
+        app:srcCompat="@drawable/header_image" />
+
+    <ImageView
+        android:id="@+id/poster_sparkling"
+        android:layout_width="@dimen/space_96"
+        android:layout_height="@dimen/space_152"
+        android:layout_marginTop="@dimen/space_200"
+        android:contentDescription="@string/poster_sparkling"
+        app:layout_constraintStart_toStartOf="@+id/guideline1"
+        app:layout_constraintTop_toTopOf="@+id/header_image"
+        app:srcCompat="@drawable/poster_sparkling" />
+
+    <androidx.constraintlayout.widget.Guideline
+        android:id="@+id/guideline1"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:orientation="vertical"
+        app:layout_constraintGuide_begin="@dimen/space_24" />
+
+    <TextView
+        android:id="@+id/song_text_view"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="@dimen/space_24"
+        android:text="@string/christmas_message"
+        android:textSize="@dimen/medium_text"
+        app:layout_constraintStart_toStartOf="@+id/guideline1"
+        app:layout_constraintTop_toBottomOf="@+id/poster_sparkling" />
+
+    <Button
+        android:id="@+id/let_it_snow_bottom"
+        android:layout_width="@dimen/space_176"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="@dimen/space_24"
+        android:layout_marginEnd="@dimen/space_8"
+        android:background="@color/pink"
+        android:text="@string/let_it_snow"
+        android:textColor="@color/white"
+        app:layout_constraintEnd_toStartOf="@+id/jingle_bells_button"
+        app:layout_constraintStart_toStartOf="@+id/guideline1"
+        app:layout_constraintTop_toBottomOf="@+id/song_text_view" />
+
+    <Button
+        android:id="@+id/jingle_bells_button"
+        android:layout_width="@dimen/space_176"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="@dimen/space_24"
+        android:layout_marginEnd="@dimen/space_24"
+        android:background="@color/pink"
+        android:text="@string/jingle_bells"
+        android:textColor="@color/white"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toEndOf="@+id/let_it_snow_bottom"
+        app:layout_constraintTop_toBottomOf="@+id/song_text_view" />
+
+    <TextView
+        android:id="@+id/happy_holidays_text_view"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="@dimen/medium_space"
+        android:text="@string/happy_holidays"
+        android:textColor="@color/black"
+        android:textSize="@dimen/text_24"
+        android:textStyle="bold"
+        app:layout_constraintStart_toStartOf="@+id/guideline2"
+        app:layout_constraintTop_toBottomOf="@+id/header_image" />
+
+    <TextView
+        android:id="@+id/from_magda_text_view"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="@dimen/space_8"
+        android:text="@string/from_magda"
+        android:textColor="@color/black"
+        android:textSize="@dimen/medium_text"
+        app:layout_constraintStart_toStartOf="@+id/guideline2"
+        app:layout_constraintTop_toBottomOf="@+id/happy_holidays_text_view" />
+
+    <androidx.constraintlayout.widget.Guideline
+        android:id="@+id/guideline2"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:orientation="vertical"
+        app:layout_constraintGuide_begin="@dimen/space_136" />
+
+    <RatingBar
+        android:id="@+id/ratingBar"
+        style="@style/Widget.AppCompat.RatingBar.Indicator"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginEnd="@dimen/medium_space"
+        android:numStars="1"
+        android:rating="1"
+        android:theme="@style/RatingBar"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintTop_toTopOf="@+id/happy_holidays_text_view" />
+
+</androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file
diff --git a/app/src/main/res/values/colors.xml b/app/src/main/res/values/colors.xml
index d8ce349..05d2709 100644
--- a/app/src/main/res/values/colors.xml
+++ b/app/src/main/res/values/colors.xml
@@ -8,4 +8,6 @@
     <color name="black">#FF000000</color>
     <color name="white">#FFFFFFFF</color>
     <color name="red">#ff3412</color>
+    <color name="duskYellow">#FFC922</color>
+    <color name="pink">#FF1493</color>
 </resources>
\ No newline at end of file
diff --git a/app/src/main/res/values/dimens.xml b/app/src/main/res/values/dimens.xml
index e8b2c28..decdcb3 100644
--- a/app/src/main/res/values/dimens.xml
+++ b/app/src/main/res/values/dimens.xml
@@ -1,7 +1,16 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
-    <dimen name="medium_text">23sp</dimen>
+    <dimen name="medium_text">18sp</dimen>
     <dimen name="medium_space">16dp</dimen>
     <dimen name="space_128">128dp</dimen>
     <dimen name="space_64">64dp</dimen>
+    <dimen name="space_136">136dp</dimen>
+    <dimen name="space_8">8dp</dimen>
+    <dimen name="text_24">24sp</dimen>
+    <dimen name="space_24">24dp</dimen>
+    <dimen name="space_176">176dp</dimen>
+    <dimen name="space_152">152dp</dimen>
+    <dimen name="space_200">200dp</dimen>
+    <dimen name="space_96">96dp</dimen>
+    <dimen name="space_272">272dp</dimen>
 </resources>
\ No newline at end of file
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index b363a5c..35af1ec 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -1,5 +1,5 @@
 <resources>
-    <string name="app_name">Curs Android Fundamentals</string>
+    <string name="app_name">Android Developer Fundamentals</string>
     <string name="hello_world_from_android">Hello World from Android!</string>
     <string name="this_is_my_first_textview">This is my first TextView</string>
     <string name="i_am_a_button">I am a button</string>
@@ -58,4 +58,11 @@ Ut fermentum feugiat lorem sed ultrices. Phasellus et mattis diam. Sed faucibus
     <string name="start_constraint_activity">Start Constraint Activity</string>
     <string name="this_is_a_textview_in_a_constraintlayout">This is a TextView in a ConstraintLayout</string>
     <string name="this_is_a_long_text_view_content">this is a long text view content</string>
+    <string name="header_imagine">header_imagine</string>
+    <string name="poster_sparkling">poster_sparkling</string>
+    <string name="christmas_message">Have yourself a merry little Christmas, \nLet your heart be light\nFrom now on, our troubles will be out of sight</string>
+    <string name="let_it_snow">LET IT SNOW</string>
+    <string name="jingle_bells">JINGLE BELLS</string>
+    <string name="happy_holidays">Happy Holidays!</string>
+    <string name="from_magda">From Magda</string>
 </resources>
\ No newline at end of file
diff --git a/app/src/main/res/values/themes.xml b/app/src/main/res/values/themes.xml
index 2868c13..008f6ee 100644
--- a/app/src/main/res/values/themes.xml
+++ b/app/src/main/res/values/themes.xml
@@ -1,6 +1,6 @@
 <resources xmlns:tools="http://schemas.android.com/tools">
     <!-- Base application theme. -->
-    <style name="Theme.AndroidFundamentalsMai2021" parent="Theme.MaterialComponents.DayNight.DarkActionBar">
+    <style name="Theme.AndroidFundamentalsMai2021" parent="Theme.AppCompat.Light">
         <!-- Primary brand color. -->
         <item name="colorPrimary">@color/purple_500</item>
         <item name="colorPrimaryVariant">@color/purple_700</item>
@@ -13,4 +13,7 @@
         <item name="android:statusBarColor" tools:targetApi="l">?attr/colorPrimaryVariant</item>
         <!-- Customize your theme here. -->
     </style>
+    <style name="RatingBar" parent="Theme.AppCompat">
+        <item name="colorControlActivated">@color/duskYellow</item>
+    </style>
 </resources>
\ No newline at end of file