diff --git a/AnkiDroid/src/main/res/layout/reviewer_topbar.xml b/AnkiDroid/src/main/res/layout/reviewer_topbar.xml
index f679be40bc..65efb134db 100644
--- a/AnkiDroid/src/main/res/layout/reviewer_topbar.xml
+++ b/AnkiDroid/src/main/res/layout/reviewer_topbar.xml
@@ -4,8 +4,8 @@
     android:id="@+id/top_bar"
         android:layout_width="fill_parent"
         android:layout_height="wrap_content"
-        android:paddingLeft="9dp"
-        android:paddingRight="10dp"
+        android:paddingLeft="@dimen/side_margin"
+        android:paddingRight="@dimen/side_margin"
         android:paddingTop="2dp"
         android:paddingBottom="3dp"
         android:gravity="center_vertical"
diff --git a/AnkiDroid/src/main/res/values/dimens.xml b/AnkiDroid/src/main/res/values/dimens.xml
index a014ae9b99..55f979aca7 100644
--- a/AnkiDroid/src/main/res/values/dimens.xml
+++ b/AnkiDroid/src/main/res/values/dimens.xml
@@ -1,5 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources xmlns:tools="http://schemas.android.com/tools" tools:ignore="UnusedResources">
+    <!-- Material UI side margin: http://web.archive.org/web/20180105203433if_/https://material.io/guidelines/layout/metrics-keylines.html#metrics-keylines-keylines-spacing -->
+    <dimen name="side_margin">16dp</dimen>
     <dimen name="touch_target">48dp</dimen>
     <dimen name="default_width">56dp</dimen>
     <dimen name="keyline_1">16dp</dimen>