diff --git a/res/drawable/metro_button_blue.xml b/res/drawable/metro_button_blue.xml
new file mode 100644
index 00000000..5a23942f
--- /dev/null
+++ b/res/drawable/metro_button_blue.xml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<selector xmlns:a="http://schemas.android.com/apk/res/android">
+
+	<item a:state_pressed="true"
+		  a:drawable="@drawable/metro_button_pressed"/>
+
+	<item a:drawable="@drawable/metro_button_blue_shape"/>
+
+</selector>
\ No newline at end of file
diff --git a/res/drawable/metro_button_blue_shape.xml b/res/drawable/metro_button_blue_shape.xml
new file mode 100644
index 00000000..d559802b
--- /dev/null
+++ b/res/drawable/metro_button_blue_shape.xml
@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2007 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+
+<shape xmlns:android="http://schemas.android.com/apk/res/android">
+    <gradient android:startColor="#10648c" android:endColor="#10648c"/>
+    <corners android:radius="1dp" />
+</shape>
\ No newline at end of file
diff --git a/res/drawable/metro_button_pressed.xml b/res/drawable/metro_button_pressed.xml
index 0e91626c..fc25288a 100644
--- a/res/drawable/metro_button_pressed.xml
+++ b/res/drawable/metro_button_pressed.xml
@@ -15,6 +15,6 @@
 -->
 
 <shape xmlns:android="http://schemas.android.com/apk/res/android">
-    <gradient android:startColor="#959595" android:endColor="#959595"/>
+    <gradient android:startColor="#1aa1e1" android:endColor="#1aa1e1"/>
     <corners android:radius="1dp" />
 </shape>
\ No newline at end of file
diff --git a/res/layout/calc_division_button.xml b/res/layout/calc_division_button.xml
index 82ffaf46..148a7431 100644
--- a/res/layout/calc_division_button.xml
+++ b/res/layout/calc_division_button.xml
@@ -13,5 +13,5 @@
 													   a:text="/"
 													   c:textDown="√"
 													   c:directionTextScale="0.5"
-													   style="?digitButtonStyle"
+													   style="?operationButtonStyle"
 													   a:onClick="digitButtonClickHandler"/>
\ No newline at end of file
diff --git a/res/layout/calc_multiplication_button.xml b/res/layout/calc_multiplication_button.xml
index ab577d24..ea5831ae 100644
--- a/res/layout/calc_multiplication_button.xml
+++ b/res/layout/calc_multiplication_button.xml
@@ -13,6 +13,6 @@
 													   c:textUp="^"
 													   c:textDown="^2"
 													   c:textLeft="Π"
-													   style="?digitButtonStyle"
+													   style="?operationButtonStyle"
 													   c:directionTextScale="0.5"
 													   a:onClick="digitButtonClickHandler"/>
\ No newline at end of file
diff --git a/res/layout/calc_plus_button.xml b/res/layout/calc_plus_button.xml
index cc6be7ba..b01f8822 100644
--- a/res/layout/calc_plus_button.xml
+++ b/res/layout/calc_plus_button.xml
@@ -12,5 +12,5 @@
 													   c:textUp="°"
 													   c:textDown="E"
 													   a:text="+"
-													   style="?digitButtonStyle"
+													   style="?operationButtonStyle"
 													   a:onClick="digitButtonClickHandler"/>
\ No newline at end of file
diff --git a/res/layout/calc_subtraction_button.xml b/res/layout/calc_subtraction_button.xml
index 4ce38f8b..b10a691d 100644
--- a/res/layout/calc_subtraction_button.xml
+++ b/res/layout/calc_subtraction_button.xml
@@ -11,5 +11,5 @@
 													   c:textDown="∂,…"
 													   a:text="-"
 													   c:directionTextScale="0.5"
-													   style="?digitButtonStyle"
+													   style="?operationButtonStyle"
 													   a:onClick="digitButtonClickHandler"/>
\ No newline at end of file
diff --git a/res/values/attributes.xml b/res/values/attributes.xml
index 8932dfe6..7d2719a2 100644
--- a/res/values/attributes.xml
+++ b/res/values/attributes.xml
@@ -4,5 +4,6 @@
 	<attr name="digitButtonStyle" format="reference" />
 	<attr name="controlButtonStyle" format="reference" />
 	<attr name="controlImageButtonStyle" format="reference" />
+	<attr name="operationButtonStyle" format="reference" />
 
 </resources>
diff --git a/res/values/styles-default-theme.xml b/res/values/styles-default-theme.xml
index f06b6f46..8357fde0 100644
--- a/res/values/styles-default-theme.xml
+++ b/res/values/styles-default-theme.xml
@@ -12,6 +12,10 @@
 
 	<style name="default_control_button_style" parent="button_style"/>
 
+	<style name="default_operation_button_style" parent="default_digit_button_style">
+		<item name="android:textColor">@color/button_operator_text_color</item>
+	</style>
+
 	<style name="default_control_image_button_style" parent="default_control_button_style">
 		<item name="android:padding">6dp</item>
 	</style>
@@ -20,5 +24,6 @@
 		<item name="digitButtonStyle">@style/default_digit_button_style</item>
 		<item name="controlButtonStyle">@style/default_control_button_style</item>
 		<item name="controlImageButtonStyle">@style/default_control_image_button_style</item>
+		<item name="operationButtonStyle">@style/default_operation_button_style</item>
 	</style>
 </resources>
\ No newline at end of file
diff --git a/res/values/styles-light-blue-theme.xml b/res/values/styles-light-blue-theme.xml
index ebff5daf..8e788923 100644
--- a/res/values/styles-light-blue-theme.xml
+++ b/res/values/styles-light-blue-theme.xml
@@ -15,6 +15,10 @@
 		<item name="android:background">@drawable/blue_button_dark</item>
 	</style>
 
+	<style name="light_blue_operation_button_style" parent="light_blue_digit_button_style">
+		<item name="android:textColor">@color/button_operator_text_color</item>
+	</style>
+
 	<style name="light_blue_control_image_button_style" parent="light_blue_control_button_style">
 		<item name="android:padding">6dp</item>
 	</style>
@@ -23,6 +27,7 @@
 		<item name="digitButtonStyle">@style/light_blue_digit_button_style</item>
 		<item name="controlButtonStyle">@style/light_blue_control_button_style</item>
 		<item name="controlImageButtonStyle">@style/light_blue_control_image_button_style</item>
+		<item name="operationButtonStyle">@style/light_blue_operation_button_style</item>
 	</style>
 
 </resources>
\ No newline at end of file
diff --git a/res/values/styles-metro-theme.xml b/res/values/styles-metro-theme.xml
index 9b0f6922..608543b6 100644
--- a/res/values/styles-metro-theme.xml
+++ b/res/values/styles-metro-theme.xml
@@ -10,6 +10,10 @@
 		<item name="android:background">@drawable/metro_button_light</item>
 	</style>
 
+	<style name="metro_operation_button_style" parent="metro_digit_button_style">
+		<item name="android:background">@drawable/metro_button_blue</item>
+	</style>
+
 	<style name="metro_control_image_button_style" parent="metro_control_button_style">
 		<item name="android:padding">6dp</item>
 	</style>
@@ -18,6 +22,7 @@
 		<item name="digitButtonStyle">@style/metro_digit_button_style</item>
 		<item name="controlButtonStyle">@style/metro_control_button_style</item>
 		<item name="controlImageButtonStyle">@style/metro_control_image_button_style</item>
+		<item name="operationButtonStyle">@style/metro_operation_button_style</item>
 	</style>
 
 </resources>
\ No newline at end of file
diff --git a/res/values/styles-violet-theme.xml b/res/values/styles-violet-theme.xml
index 551a367f..3d306c84 100644
--- a/res/values/styles-violet-theme.xml
+++ b/res/values/styles-violet-theme.xml
@@ -10,6 +10,10 @@
 		<item name="android:background">@drawable/violet_button</item>
 	</style>
 
+	<style name="violet_operation_button_style" parent="violet_digit_button_style">
+			<item name="android:textColor">@color/button_operator_text_color</item>
+	</style>
+
 	<style name="violet_control_button_style" parent="button_style">
 		<item name="android:background">@drawable/violet_button_dark</item>
 	</style>
@@ -22,5 +26,6 @@
 		<item name="digitButtonStyle">@style/violet_digit_button_style</item>
 		<item name="controlButtonStyle">@style/violet_control_button_style</item>
 		<item name="controlImageButtonStyle">@style/violet_control_image_button_style</item>
+		<item name="operationButtonStyle">@style/violet_operation_button_style</item>
 	</style>
 </resources>
\ No newline at end of file