diff --git a/app/src/main/res/color/btn_nav_left_icon_tint.xml b/app/src/main/res/color/btn_nav_left_icon_tint.xml
new file mode 100644
index 0000000..1a2d916
--- /dev/null
+++ b/app/src/main/res/color/btn_nav_left_icon_tint.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:color="#FFFFFFFF"/>
+</selector>
diff --git a/app/src/main/res/color/btn_nav_left_ripple.xml b/app/src/main/res/color/btn_nav_left_ripple.xml
new file mode 100644
index 0000000..726fcd0
--- /dev/null
+++ b/app/src/main/res/color/btn_nav_left_ripple.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:alpha="0.2" android:color="#FFFFFF"/>
+</selector>
diff --git a/app/src/main/res/color/btn_nav_left_tint.xml b/app/src/main/res/color/btn_nav_left_tint.xml
new file mode 100644
index 0000000..1d171f5
--- /dev/null
+++ b/app/src/main/res/color/btn_nav_left_tint.xml
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:alpha="0.85" android:color="#334B5A" android:state_pressed="true"/>
+    <item android:color="#385266"/>
+</selector>
diff --git a/app/src/main/res/color/btn_nav_right_icon_tint.xml b/app/src/main/res/color/btn_nav_right_icon_tint.xml
new file mode 100644
index 0000000..1a2d916
--- /dev/null
+++ b/app/src/main/res/color/btn_nav_right_icon_tint.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:color="#FFFFFFFF"/>
+</selector>
diff --git a/app/src/main/res/color/btn_nav_right_ripple.xml b/app/src/main/res/color/btn_nav_right_ripple.xml
new file mode 100644
index 0000000..726fcd0
--- /dev/null
+++ b/app/src/main/res/color/btn_nav_right_ripple.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:alpha="0.2" android:color="#FFFFFF"/>
+</selector>
diff --git a/app/src/main/res/color/btn_nav_right_tint.xml b/app/src/main/res/color/btn_nav_right_tint.xml
new file mode 100644
index 0000000..e9583a1
--- /dev/null
+++ b/app/src/main/res/color/btn_nav_right_tint.xml
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:alpha="0.85" android:color="#2F855A" android:state_pressed="true"/>
+    <item android:color="#339966"/>
+</selector>
diff --git a/app/src/main/res/drawable/ic_chevron_left.xml b/app/src/main/res/drawable/ic_chevron_left.xml
new file mode 100644
index 0000000..a0c6752
--- /dev/null
+++ b/app/src/main/res/drawable/ic_chevron_left.xml
@@ -0,0 +1,11 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="32dp" android:height="32dp"
+    android:viewportWidth="24" android:viewportHeight="24">
+    <path
+        android:fillColor="@android:color/transparent"
+        android:strokeColor="#FFFFFFFF"
+        android:strokeWidth="2.8"
+        android:strokeLineCap="round"
+        android:strokeLineJoin="round"
+        android:pathData="M15,6 L9,12 L15,18" />
+</vector>
diff --git a/app/src/main/res/drawable/ic_chevron_right.xml b/app/src/main/res/drawable/ic_chevron_right.xml
new file mode 100644
index 0000000..a93db23
--- /dev/null
+++ b/app/src/main/res/drawable/ic_chevron_right.xml
@@ -0,0 +1,11 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="32dp" android:height="32dp"
+    android:viewportWidth="24" android:viewportHeight="24">
+    <path
+        android:fillColor="@android:color/transparent"
+        android:strokeColor="#FFFFFFFF"
+        android:strokeWidth="2.8"
+        android:strokeLineCap="round"
+        android:strokeLineJoin="round"
+        android:pathData="M9,6 L15,12 L9,18" />
+</vector>
diff --git a/app/src/main/res/layout/client_coach_code_question.xml b/app/src/main/res/layout/client_coach_code_question.xml
index bef927a..311f80d 100644
--- a/app/src/main/res/layout/client_coach_code_question.xml
+++ b/app/src/main/res/layout/client_coach_code_question.xml
@@ -9,50 +9,42 @@
     tools:layout_editor_absoluteX="11dp"
     tools:layout_editor_absoluteY="107dp">
 
-    <Button
+    <com.google.android.material.button.MaterialButton
         android:id="@+id/Qprev"
-        android:layout_width="0dp"
-        android:layout_height="0dp"
-        android:layout_marginEnd="70dp"
-        android:layout_marginBottom="12dp"
-        android:autoSizeMaxTextSize="48sp"
-        android:autoSizeMinTextSize="12sp"
-        android:autoSizeStepGranularity="2sp"
-        android:autoSizeTextType="uniform"
-        android:gravity="center"
-        android:paddingStart="12dp"
-        android:paddingEnd="12dp"
-        android:tag="previous"
+        android:layout_width="@dimen/nav_btn_size"
+        android:layout_height="@dimen/nav_btn_size"
+        android:layout_marginStart="20dp"
+        android:layout_marginBottom="16dp"
+        android:text=""
+        android:textAllCaps="false"
+        app:icon="@drawable/ic_chevron_left"
+        app:iconTint="@color/btn_nav_left_icon_tint"
+        app:iconSize="@dimen/nav_icon_size"
+        app:iconPadding="0dp"
+        app:cornerRadius="999dp"
+        app:backgroundTint="@color/btn_nav_left_tint"
+        app:rippleColor="@color/btn_nav_left_ripple"
         app:layout_constraintBottom_toBottomOf="parent"
-        app:layout_constraintEnd_toStartOf="@id/Qnext"
-        app:layout_constraintHeight_percent="0.07"
-        app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toTopOf="parent"
-        app:layout_constraintVertical_bias="1.0"
-        app:layout_constraintWidth_percent="0.30" />
+        app:layout_constraintStart_toStartOf="parent" />
 
-    <Button
+    <!-- Weiter -->
+    <com.google.android.material.button.MaterialButton
         android:id="@+id/Qnext"
-        android:layout_width="0dp"
-        android:layout_height="0dp"
-        android:layout_marginBottom="12dp"
-        android:layout_marginStart="70dp"
-        android:autoSizeMaxTextSize="48sp"
-        android:autoSizeMinTextSize="12sp"
-        android:autoSizeStepGranularity="2sp"
-        android:autoSizeTextType="uniform"
-        android:gravity="center"
-        android:paddingStart="12dp"
-        android:paddingEnd="12dp"
-        android:tag="next"
+        android:layout_width="@dimen/nav_btn_size"
+        android:layout_height="@dimen/nav_btn_size"
+        android:layout_marginEnd="20dp"
+        android:layout_marginBottom="16dp"
+        android:text=""
+        android:textAllCaps="false"
+        app:icon="@drawable/ic_chevron_right"
+        app:iconTint="@color/btn_nav_right_icon_tint"
+        app:iconSize="@dimen/nav_icon_size"
+        app:iconPadding="0dp"
+        app:cornerRadius="999dp"
+        app:backgroundTint="@color/btn_nav_right_tint"
+        app:rippleColor="@color/btn_nav_right_ripple"
         app:layout_constraintBottom_toBottomOf="parent"
-        app:layout_constraintEnd_toEndOf="parent"
-        app:layout_constraintHeight_percent="0.07"
-        app:layout_constraintStart_toEndOf="@id/Qprev"
-        app:layout_constraintTop_toTopOf="parent"
-        app:layout_constraintVertical_bias="1.0"
-        app:layout_constraintWidth_percent="0.30" />
-
+        app:layout_constraintEnd_toEndOf="parent" />
 
     <EditText
         android:id="@+id/client_code"
diff --git a/app/src/main/res/layout/radio_question.xml b/app/src/main/res/layout/radio_question.xml
index dfadfe1..a7a728f 100644
--- a/app/src/main/res/layout/radio_question.xml
+++ b/app/src/main/res/layout/radio_question.xml
@@ -9,49 +9,45 @@
     tools:layout_editor_absoluteX="11dp"
     tools:layout_editor_absoluteY="107dp">
 
-    <Button
+    <!-- Zurück -->
+    <com.google.android.material.button.MaterialButton
         android:id="@+id/Qprev"
-        android:layout_width="0dp"
-        android:layout_height="0dp"
-        android:layout_marginEnd="70dp"
-        android:layout_marginBottom="12dp"
-        android:autoSizeMaxTextSize="48sp"
-        android:autoSizeMinTextSize="12sp"
-        android:autoSizeStepGranularity="2sp"
-        android:autoSizeTextType="uniform"
-        android:gravity="center"
-        android:paddingStart="12dp"
-        android:paddingEnd="12dp"
-        android:tag="previous"
+        android:layout_width="@dimen/nav_btn_size"
+        android:layout_height="@dimen/nav_btn_size"
+        android:layout_marginStart="20dp"
+        android:layout_marginBottom="16dp"
+        android:text=""
+        android:textAllCaps="false"
+        app:icon="@drawable/ic_chevron_left"
+        app:iconTint="@color/btn_nav_left_icon_tint"
+        app:iconSize="@dimen/nav_icon_size"
+        app:iconPadding="0dp"
+        app:cornerRadius="999dp"
+        app:backgroundTint="@color/btn_nav_left_tint"
+        app:rippleColor="@color/btn_nav_left_ripple"
         app:layout_constraintBottom_toBottomOf="parent"
-        app:layout_constraintEnd_toStartOf="@id/Qnext"
-        app:layout_constraintHeight_percent="0.07"
-        app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toTopOf="parent"
-        app:layout_constraintVertical_bias="1.0"
-        app:layout_constraintWidth_percent="0.30" />
+        app:layout_constraintStart_toStartOf="parent" />
 
-    <Button
+    <!-- Weiter -->
+    <com.google.android.material.button.MaterialButton
         android:id="@+id/Qnext"
-        android:layout_width="0dp"
-        android:layout_height="0dp"
-        android:layout_marginBottom="12dp"
-        android:layout_marginStart="70dp"
-        android:autoSizeMaxTextSize="48sp"
-        android:autoSizeMinTextSize="12sp"
-        android:autoSizeStepGranularity="2sp"
-        android:autoSizeTextType="uniform"
-        android:gravity="center"
-        android:paddingStart="12dp"
-        android:paddingEnd="12dp"
-        android:tag="next"
+        android:layout_width="@dimen/nav_btn_size"
+        android:layout_height="@dimen/nav_btn_size"
+        android:layout_marginEnd="20dp"
+        android:layout_marginBottom="16dp"
+        android:text=""
+        android:textAllCaps="false"
+        app:icon="@drawable/ic_chevron_right"
+        app:iconTint="@color/btn_nav_right_icon_tint"
+        app:iconSize="@dimen/nav_icon_size"
+        app:iconPadding="0dp"
+        app:cornerRadius="999dp"
+        app:backgroundTint="@color/btn_nav_right_tint"
+        app:rippleColor="@color/btn_nav_right_ripple"
         app:layout_constraintBottom_toBottomOf="parent"
-        app:layout_constraintEnd_toEndOf="parent"
-        app:layout_constraintHeight_percent="0.07"
-        app:layout_constraintStart_toEndOf="@id/Qprev"
-        app:layout_constraintTop_toTopOf="parent"
-        app:layout_constraintVertical_bias="1.0"
-        app:layout_constraintWidth_percent="0.30" />
+        app:layout_constraintEnd_toEndOf="parent" />
+
+
 
     <!-- SCROLLBEREICH für die Radio-Optionen:
          füllt den Platz zwischen Frage und Buttons, scrollt bei Bedarf -->
diff --git a/app/src/main/res/values/dimens.xml b/app/src/main/res/values/dimens.xml
new file mode 100644
index 0000000..c7fb1dc
--- /dev/null
+++ b/app/src/main/res/values/dimens.xml
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <dimen name="nav_btn_size">64dp</dimen>
+    <dimen name="nav_icon_size">28dp</dimen>
+</resources>