diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
index dfde6fd..b7b7e16 100644
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -3,12 +3,12 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:orientation="vertical"
     tools:context="sushi.hardcore.droidfs.MainActivity">
 
     <include layout="@layout/toolbar"/>
 
-
     <sushi.hardcore.droidfs.widgets.ColoredImageView
         android:id="@+id/image_logo"
         android:layout_width="match_parent"
@@ -17,40 +17,44 @@
         android:src="@drawable/logo"
         android:layout_weight="1"/>
 
-    <LinearLayout
-        android:id="@+id/aaa"
+    <androidx.constraintlayout.widget.ConstraintLayout
         android:layout_width="match_parent"
         android:layout_height="0dp"
-        android:orientation="vertical"
         android:layout_weight="1">
 
         <androidx.appcompat.widget.AppCompatButton
+            android:id="@+id/button_open"
             android:layout_width="match_parent"
             android:layout_height="@dimen/main_activity_button_height"
+            app:layout_constraintTop_toTopOf="parent"
+            app:layout_constraintBottom_toTopOf="@id/button_create"
             android:layout_marginHorizontal="@dimen/main_activity_button_hor_margin"
-            android:layout_marginVertical="@dimen/main_activity_button_ver_margin"
             android:onClick="onClickOpen"
             android:text="@string/open_volume"
             style="@style/button"/>
 
         <androidx.appcompat.widget.AppCompatButton
+            android:id="@+id/button_create"
             android:layout_width="match_parent"
             android:layout_height="@dimen/main_activity_button_height"
+            app:layout_constraintTop_toBottomOf="@id/button_open"
+            app:layout_constraintBottom_toTopOf="@id/button_change_password"
             android:layout_marginHorizontal="@dimen/main_activity_button_hor_margin"
-            android:layout_marginVertical="@dimen/main_activity_button_ver_margin"
             android:onClick="onClickCreate"
             android:text="@string/create_volume"
             style="@style/button"/>
 
         <androidx.appcompat.widget.AppCompatButton
+            android:id="@+id/button_change_password"
             android:layout_width="match_parent"
             android:layout_height="@dimen/main_activity_button_height"
+            app:layout_constraintTop_toBottomOf="@id/button_create"
+            app:layout_constraintBottom_toBottomOf="parent"
             android:layout_marginHorizontal="@dimen/main_activity_button_hor_margin"
-            android:layout_marginVertical="@dimen/main_activity_button_ver_margin"
             android:onClick="onClickChangePassword"
             android:text="@string/change_volume_password"
             style="@style/button"/>
 
-    </LinearLayout>
+    </androidx.constraintlayout.widget.ConstraintLayout>
 
 </LinearLayout>
\ 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 4bdc481..8cd7df4 100644
--- a/app/src/main/res/values/dimens.xml
+++ b/app/src/main/res/values/dimens.xml
@@ -2,7 +2,6 @@
 <resources>
     <dimen name="main_activity_button_height">60dp</dimen>
     <dimen name="main_activity_button_hor_margin">50dp</dimen>
-    <dimen name="main_activity_button_ver_margin">20dp</dimen>
     <dimen name="create_activity_label_width">100dp</dimen>
     <dimen name="edit_text_label_text_size">15sp</dimen>
     <dimen name="open_activity_label_width">90dp</dimen>