diff --git a/app/src/main/res/layout-land/activity_about.xml b/app/src/main/res/layout-land/activity_about.xml
index 97b5716..c7ac404 100644
--- a/app/src/main/res/layout-land/activity_about.xml
+++ b/app/src/main/res/layout-land/activity_about.xml
@@ -3,13 +3,13 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    android:background="#FFFFFF">
+    android:background="?attr/lightestBackGround">
 
     <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
         xmlns:tools="http://schemas.android.com/tools"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:background="#FFFFFF"
+        android:background="?attr/lightestBackGround"
         android:id="@+id/main_content"
         android:fitsSystemWindows="true"
         android:orientation="vertical"
diff --git a/app/src/main/res/layout-land/activity_main_menu.xml b/app/src/main/res/layout-land/activity_main_menu.xml
index bc24413..804b73a 100644
--- a/app/src/main/res/layout-land/activity_main_menu.xml
+++ b/app/src/main/res/layout-land/activity_main_menu.xml
@@ -119,7 +119,7 @@
                     style="@style/RatingBar"/>
 
                 <Button
-                    android:textColor="@color/white"
+                    android:textColor="?attr/lightestFontColor"
                     android:layout_width="match_parent"
                     android:layout_height="wrap_content"
                     android:layout_marginTop="20dp"
@@ -137,7 +137,7 @@
                     android:background="@drawable/standalone_button"/>
 
                 <Button
-                    android:textColor="@color/white"
+                    android:textColor="?attr/lightestFontColor"
                     android:layout_width="match_parent"
                     android:layout_height="wrap_content"
                     android:layout_marginTop="@dimen/activity_vertical_margin"
@@ -164,7 +164,7 @@
         android:layout_height="match_parent"
         android:layout_gravity="start"
         android:fitsSystemWindows="true"
-        android:background="@color/white"
+        android:background="?attr/lightestBackGround"
         app:menu="@menu/menu_drawer_main"
         app:headerLayout="@layout/nav_header" />
 
diff --git a/app/src/main/res/layout-small/activity_main_menu.xml b/app/src/main/res/layout-small/activity_main_menu.xml
index d989504..aa87549 100644
--- a/app/src/main/res/layout-small/activity_main_menu.xml
+++ b/app/src/main/res/layout-small/activity_main_menu.xml
@@ -118,7 +118,7 @@
                 style="@style/RatingBar"/>
 
             <Button
-                android:textColor="@color/white"
+                android:textColor="?attr/lightestFontColor"
                 android:layout_width="match_parent"
                 android:layout_height="0dp"
                 android:layout_marginLeft="@dimen/main_button_padding"
@@ -136,7 +136,7 @@
                 android:background="@drawable/standalone_button"/>
 
             <Button
-                android:textColor="@color/white"
+                android:textColor="?attr/lightestFontColor"
                 android:layout_marginTop="20dp"
                 android:layout_width="match_parent"
                 android:layout_height="0dp"
@@ -237,7 +237,7 @@
         android:layout_height="match_parent"
         android:layout_gravity="start"
         android:fitsSystemWindows="true"
-        android:background="@color/white"
+        android:background="?attr/lightestBackGround"
         app:menu="@menu/menu_drawer_main"
         app:headerLayout="@layout/nav_header" />
 
diff --git a/app/src/main/res/layout-xlarge-land/activity_about.xml b/app/src/main/res/layout-xlarge-land/activity_about.xml
index 7944f3d..5580f18 100644
--- a/app/src/main/res/layout-xlarge-land/activity_about.xml
+++ b/app/src/main/res/layout-xlarge-land/activity_about.xml
@@ -3,13 +3,13 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    android:background="#FFFFFF">
+    android:background="?attr/lightestBackGround">
 
     <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
         xmlns:tools="http://schemas.android.com/tools"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:background="#FFFFFF"
+        android:background="?attr/lightestBackGround"
         android:id="@+id/main_content"
         android:fitsSystemWindows="true"
         android:orientation="vertical"
diff --git a/app/src/main/res/layout-xlarge/activity_about.xml b/app/src/main/res/layout-xlarge/activity_about.xml
index 6ddebfb..3f69cbc 100644
--- a/app/src/main/res/layout-xlarge/activity_about.xml
+++ b/app/src/main/res/layout-xlarge/activity_about.xml
@@ -3,13 +3,13 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    android:background="#FFFFFF">
+    android:background="?attr/lightestBackGround">
 
     <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
         xmlns:tools="http://schemas.android.com/tools"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:background="#FFFFFF"
+        android:background="?attr/lightestBackGround"
         android:id="@+id/main_content"
         android:fitsSystemWindows="true"
         android:orientation="vertical"
diff --git a/app/src/main/res/layout-xlarge/activity_main_menu.xml b/app/src/main/res/layout-xlarge/activity_main_menu.xml
index 1f21a39..326b1d8 100644
--- a/app/src/main/res/layout-xlarge/activity_main_menu.xml
+++ b/app/src/main/res/layout-xlarge/activity_main_menu.xml
@@ -122,7 +122,7 @@
                 style="@style/RatingBar"/>
 
             <Button
-                android:textColor="@color/white"
+                android:textColor="?attr/lightestFontColor"
                 android:layout_width="match_parent"
                 android:layout_height="0dp"
                 android:layout_marginTop="@dimen/activity_vertical_margin"
@@ -141,7 +141,7 @@
                 android:background="@drawable/standalone_button"/>
 
             <Button
-                android:textColor="@color/white"
+                android:textColor="?attr/lightestFontColor"
                 android:layout_marginTop="20dp"
                 android:layout_width="match_parent"
                 android:layout_height="0dp"
@@ -235,7 +235,7 @@
         android:layout_height="match_parent"
         android:layout_gravity="start"
         android:fitsSystemWindows="true"
-        android:background="@color/white"
+        android:background="?attr/lightestBackGround"
         app:menu="@menu/menu_drawer_main"
         app:headerLayout="@layout/nav_header" />
 
diff --git a/app/src/main/res/layout/activity_about.xml b/app/src/main/res/layout/activity_about.xml
index d8cdd1d..6b992e2 100644
--- a/app/src/main/res/layout/activity_about.xml
+++ b/app/src/main/res/layout/activity_about.xml
@@ -3,13 +3,13 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    android:background="#FFFFFF">
+    android:background="?attr/lightestBackGround">
 
     <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
         xmlns:tools="http://schemas.android.com/tools"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:background="#FFFFFF"
+        android:background="?attr/lightestBackGround"
         android:id="@+id/main_content"
         android:fitsSystemWindows="true"
         android:orientation="vertical"
diff --git a/app/src/main/res/layout/activity_daily_sudoku.xml b/app/src/main/res/layout/activity_daily_sudoku.xml
index c505de0..b691388 100644
--- a/app/src/main/res/layout/activity_daily_sudoku.xml
+++ b/app/src/main/res/layout/activity_daily_sudoku.xml
@@ -120,7 +120,7 @@
                         android:layout_gravity="center_vertical"
                         android:layout_marginTop="0dp"
                         android:layout_marginBottom="50dp"
-                        android:background="@color/colorPrimary"
+                        android:background="?attr/colorPrimary"
                         android:foregroundGravity="center_vertical" />
 
                 </RelativeLayout>
@@ -216,7 +216,7 @@
                     android:layout_centerHorizontal="true"
                     android:layout_centerVertical="true"
                     android:layout_gravity="center_vertical"
-                    android:background="@color/colorPrimary"
+                    android:background="?attr/colorPrimary"
                     android:foregroundGravity="center_vertical" />
 
             </LinearLayout>
diff --git a/app/src/main/res/layout/activity_game_view.xml b/app/src/main/res/layout/activity_game_view.xml
index a7c23f5..69382ec 100644
--- a/app/src/main/res/layout/activity_game_view.xml
+++ b/app/src/main/res/layout/activity_game_view.xml
@@ -86,7 +86,7 @@
         android:fitsSystemWindows="true"
         android:layout_height="match_parent"
         android:layout_gravity="start"
-        android:background="@color/white"
+        android:background="?attr/lightestBackGround"
         app:menu="@menu/menu_drawer"
         app:headerLayout="@layout/nav_header" />
 
diff --git a/app/src/main/res/layout/activity_main_menu.xml b/app/src/main/res/layout/activity_main_menu.xml
index 8c6299b..cdf9e59 100644
--- a/app/src/main/res/layout/activity_main_menu.xml
+++ b/app/src/main/res/layout/activity_main_menu.xml
@@ -114,7 +114,7 @@
                 style="@style/RatingBar"/>
 
             <Button
-                android:textColor="@color/white"
+                android:textColor="?attr/lightestFontColor"
                 android:layout_width="match_parent"
                 android:layout_height="0dp"
                 android:layout_marginLeft="@dimen/main_button_padding"
@@ -131,7 +131,7 @@
                 android:background="@drawable/standalone_button"/>
 
             <Button
-                android:textColor="@color/white"
+                android:textColor="?attr/lightestFontColor"
                 android:layout_marginTop="20dp"
                 android:layout_width="match_parent"
                 android:layout_height="0dp"
@@ -232,7 +232,7 @@
         android:layout_height="match_parent"
         android:layout_gravity="start"
         android:fitsSystemWindows="true"
-        android:background="@color/white"
+        android:background="?attr/lightestBackGround"
         app:menu="@menu/menu_drawer_main"
         app:headerLayout="@layout/nav_header" />
 
diff --git a/app/src/main/res/layout/activity_tutorial.xml b/app/src/main/res/layout/activity_tutorial.xml
index 51a6287..7f3fe90 100644
--- a/app/src/main/res/layout/activity_tutorial.xml
+++ b/app/src/main/res/layout/activity_tutorial.xml
@@ -26,7 +26,7 @@
         android:layout_height="1dp"
         android:alpha=".5"
         android:layout_above="@id/layoutDots"
-        android:background="@android:color/white" />
+        android:background="?attr/lightestBackGround" />
 
     <Button
         android:id="@+id/btn_next"
@@ -36,7 +36,7 @@
         android:layout_alignParentRight="true"
         android:background="@null"
         android:text="@string/next"
-        android:textColor="@android:color/white" />
+        android:textColor="?attr/lightestFontColor" />
 
     <Button
         android:id="@+id/btn_skip"
@@ -46,6 +46,6 @@
         android:layout_alignParentLeft="true"
         android:background="@null"
         android:text="@string/skip"
-        android:textColor="@android:color/white" />
+        android:textColor="?attr/lightestFontColor" />
 
 </RelativeLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/nav_header.xml b/app/src/main/res/layout/nav_header.xml
index f4105c1..7e2fbe0 100644
--- a/app/src/main/res/layout/nav_header.xml
+++ b/app/src/main/res/layout/nav_header.xml
@@ -2,7 +2,7 @@
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
     android:layout_height="@dimen/nav_header_height"
-    android:background="@color/colorAccent"
+    android:background="?attr/colorAccent"
     android:gravity="bottom"
     android:orientation="vertical"
     android:paddingBottom="@dimen/activity_vertical_margin"
@@ -12,7 +12,7 @@
     <RelativeLayout
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:background="#ffffff"
+        android:background="?attr/lightestBackGround"
         android:paddingBottom="7dp"
         android:paddingTop="7dp">
 
@@ -29,7 +29,7 @@
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:text="@string/Sudoku"
-        android:textColor="@color/colorPrimaryDark"
+        android:textColor="?attr/colorPrimaryDark"
         android:textSize="18sp"
         android:textAppearance="@style/TextAppearance.AppCompat.Body1"
         android:layout_centerVertical="true"
diff --git a/app/src/main/res/layout/tutorial_slide1.xml b/app/src/main/res/layout/tutorial_slide1.xml
index 0bcc19d..c24dd62 100644
--- a/app/src/main/res/layout/tutorial_slide1.xml
+++ b/app/src/main/res/layout/tutorial_slide1.xml
@@ -2,7 +2,7 @@
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    android:background="@color/colorAccent">
+    android:background="?attr/colorAccent">
 
     <LinearLayout
         android:layout_width="wrap_content"
@@ -17,7 +17,7 @@
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:text="@string/slide1_heading"
-            android:textColor="@android:color/white"
+            android:textColor="?attr/lightestFontColor"
             android:textSize="@dimen/slide_title"
             android:textStyle="bold" />
 
@@ -37,7 +37,7 @@
             android:text="@string/slide1_text"
             android:textAlignment="center"
             android:gravity="center"
-            android:textColor="@android:color/white"
+            android:textColor="?attr/lightestFontColor"
             android:textSize="@dimen/slide_desc" />
 
     </LinearLayout>
diff --git a/app/src/main/res/layout/tutorial_slide2.xml b/app/src/main/res/layout/tutorial_slide2.xml
index 5d896fd..337a7d4 100644
--- a/app/src/main/res/layout/tutorial_slide2.xml
+++ b/app/src/main/res/layout/tutorial_slide2.xml
@@ -2,7 +2,7 @@
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    android:background="@color/colorAccent">
+    android:background="?attr/colorAccent">
 
     <LinearLayout
         android:layout_width="wrap_content"
@@ -16,7 +16,7 @@
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:text="@string/slide2_heading"
-            android:textColor="@android:color/white"
+            android:textColor="?attr/lightestFontColor"
             android:textSize="@dimen/slide_title"
             android:textStyle="bold" />
 
@@ -53,7 +53,7 @@
             android:paddingRight="@dimen/desc_padding"
             android:text="@string/slide2_text"
             android:textAlignment="center"
-            android:textColor="@android:color/white"
+            android:textColor="?attr/lightestFontColor"
             android:textSize="@dimen/slide_desc" />
 
     </LinearLayout>
diff --git a/app/src/main/res/layout/tutorial_slide3.xml b/app/src/main/res/layout/tutorial_slide3.xml
index b7df435..1042d98 100644
--- a/app/src/main/res/layout/tutorial_slide3.xml
+++ b/app/src/main/res/layout/tutorial_slide3.xml
@@ -2,7 +2,7 @@
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    android:background="@color/colorAccent">
+    android:background="?attr/colorAccent">
 
     <LinearLayout
         android:layout_width="wrap_content"
@@ -17,7 +17,7 @@
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:text="@string/slide3_heading"
-            android:textColor="@android:color/white"
+            android:textColor="?attr/lightestFontColor"
             android:textSize="@dimen/slide_title"
             android:textStyle="bold" />
 
@@ -30,7 +30,7 @@
             android:numStars="4"
             android:layout_marginTop="25dp"
             android:rating="1"
-            android:background="@color/white"
+            android:background="?attr/lightestFontColor"
             android:stepSize="1"
             style="@style/RatingBar"/>
 
@@ -43,7 +43,7 @@
             android:textAlignment="center"
             android:gravity="center"
             android:layout_marginTop="25dp"
-            android:textColor="@android:color/white"
+            android:textColor="?attr/lightestFontColor"
             android:textSize="@dimen/slide_desc" />
 
     </LinearLayout>