diff --git a/app/build.gradle b/app/build.gradle
index 7faeaddf3..aecd21ea7 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -102,7 +102,9 @@ dependencies {
     implementation "com.squareup.retrofit2:adapter-rxjava2:${vRetrofit}"
 
     def vOkHttp = '3.12.7'
-    implementation "com.squareup.okhttp3:okhttp:${vOkHttp}"
+    implementation("com.squareup.okhttp3:okhttp:${vOkHttp}") {
+        force = true
+    }
     implementation "com.squareup.okhttp3:logging-interceptor:${vOkHttp}"
 
     def vMoshi = '1.9.2'
diff --git a/app/src/main/java/com/topjohnwu/magisk/ui/base/BaseUIActivity.kt b/app/src/main/java/com/topjohnwu/magisk/ui/base/BaseUIActivity.kt
index 45a251626..a5a2e877d 100644
--- a/app/src/main/java/com/topjohnwu/magisk/ui/base/BaseUIActivity.kt
+++ b/app/src/main/java/com/topjohnwu/magisk/ui/base/BaseUIActivity.kt
@@ -15,7 +15,7 @@ abstract class BaseUIActivity<ViewModel : BaseViewModel, Binding : ViewDataBindi
 
     protected lateinit var binding: Binding
     protected abstract val layoutRes: Int
-    protected abstract val viewModel: ViewModel
+    abstract val viewModel: ViewModel
     protected open val themeRes: Int = R.style.MagiskTheme
 
     open val snackbarView get() = binding.root
diff --git a/app/src/main/java/com/topjohnwu/magisk/ui/base/BaseUIFragment.kt b/app/src/main/java/com/topjohnwu/magisk/ui/base/BaseUIFragment.kt
index b3ab722f9..a6992d0a7 100644
--- a/app/src/main/java/com/topjohnwu/magisk/ui/base/BaseUIFragment.kt
+++ b/app/src/main/java/com/topjohnwu/magisk/ui/base/BaseUIFragment.kt
@@ -17,7 +17,7 @@ abstract class BaseUIFragment<ViewModel : BaseViewModel, Binding : ViewDataBindi
     protected val activity get() = requireActivity() as BaseUIActivity<*, *>
     protected lateinit var binding: Binding
     protected abstract val layoutRes: Int
-    protected abstract val viewModel: ViewModel
+    abstract val viewModel: ViewModel
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
diff --git a/app/src/main/res/drawable-v21/bg_appbar.xml b/app/src/main/res/drawable-v21/bg_appbar.xml
new file mode 100644
index 000000000..264dc253c
--- /dev/null
+++ b/app/src/main/res/drawable-v21/bg_appbar.xml
@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
+    <item>
+        <shape android:shape="rectangle">
+            <solid android:color="?colorSurfaceVariant" />
+        </shape>
+    </item>
+
+    <item android:bottom="2dp">
+        <shape android:shape="rectangle">
+            <solid android:color="?colorSurface" />
+        </shape>
+    </item>
+
+</layer-list>
diff --git a/app/src/main/res/drawable-v21/bg_card.xml b/app/src/main/res/drawable-v21/bg_card.xml
new file mode 100644
index 000000000..57de59736
--- /dev/null
+++ b/app/src/main/res/drawable-v21/bg_card.xml
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="rectangle">
+    <gradient
+        android:angle="45"
+        android:endColor="?colorSurface"
+        android:startColor="?colorSurfaceVariant" />
+</shape>
\ No newline at end of file
diff --git a/app/src/main/res/drawable-v21/bg_divider_rounded_on_primary.xml b/app/src/main/res/drawable-v21/bg_divider_rounded_on_primary.xml
new file mode 100644
index 000000000..783719e7d
--- /dev/null
+++ b/app/src/main/res/drawable-v21/bg_divider_rounded_on_primary.xml
@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="rectangle">
+    <size android:height="4dp" />
+    <corners android:radius="2dp" />
+    <solid android:color="?colorOnPrimary" />
+</shape>
\ No newline at end of file
diff --git a/app/src/main/res/drawable-v21/bg_shadow.xml b/app/src/main/res/drawable-v21/bg_shadow.xml
new file mode 100644
index 000000000..4f7bd989b
--- /dev/null
+++ b/app/src/main/res/drawable-v21/bg_shadow.xml
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="rectangle">
+    <gradient
+        android:angle="270"
+        android:endColor="?colorSurfaceVariant"
+        android:startColor="@android:color/transparent" />
+</shape>
\ No newline at end of file
diff --git a/app/src/main/res/drawable-v21/fast_scroll_thumb.xml b/app/src/main/res/drawable-v21/fast_scroll_thumb.xml
new file mode 100644
index 000000000..19c3590fa
--- /dev/null
+++ b/app/src/main/res/drawable-v21/fast_scroll_thumb.xml
@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?>
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <item android:state_pressed="true">
+        <shape android:shape="rectangle">
+            <corners android:radius="@dimen/r1" />
+            <solid android:color="?colorOnSurfaceVariant" />
+            <size android:width="5dp" android:height="5dp" />
+        </shape>
+    </item>
+    <item>
+        <shape android:shape="rectangle">
+            <corners android:radius="@dimen/r1" />
+            <solid android:color="?colorOnSurfaceVariant" />
+            <size android:width="5dp" android:height="5dp" />
+        </shape>
+    </item>
+
+</selector>
diff --git a/app/src/main/res/drawable-v21/progress_determinate.xml b/app/src/main/res/drawable-v21/progress_determinate.xml
new file mode 100644
index 000000000..95b275b5d
--- /dev/null
+++ b/app/src/main/res/drawable-v21/progress_determinate.xml
@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <item android:id="@android:id/background">
+        <shape>
+            <solid android:color="@android:color/transparent" />
+        </shape>
+    </item>
+
+    <item android:id="@android:id/secondaryProgress">
+        <clip>
+            <shape>
+                <solid android:color="?colorSecondary" />
+            </shape>
+        </clip>
+    </item>
+
+    <item android:id="@android:id/progress">
+        <clip>
+            <shape>
+                <solid android:color="?colorPrimary" />
+            </shape>
+        </clip>
+    </item>
+
+</layer-list>
\ No newline at end of file
diff --git a/app/src/main/res/drawable/bg_appbar.xml b/app/src/main/res/drawable/bg_appbar.xml
index 264dc253c..9e8232951 100644
--- a/app/src/main/res/drawable/bg_appbar.xml
+++ b/app/src/main/res/drawable/bg_appbar.xml
@@ -2,13 +2,13 @@
 <layer-list xmlns:android="http://schemas.android.com/apk/res/android">
     <item>
         <shape android:shape="rectangle">
-            <solid android:color="?colorSurfaceVariant" />
+            <solid android:color="@color/defColorSurfaceVariant" />
         </shape>
     </item>
 
     <item android:bottom="2dp">
         <shape android:shape="rectangle">
-            <solid android:color="?colorSurface" />
+            <solid android:color="@color/defColorSurface" />
         </shape>
     </item>
 
diff --git a/app/src/main/res/drawable/bg_card.xml b/app/src/main/res/drawable/bg_card.xml
index 57de59736..66b0213d7 100644
--- a/app/src/main/res/drawable/bg_card.xml
+++ b/app/src/main/res/drawable/bg_card.xml
@@ -3,6 +3,6 @@
     android:shape="rectangle">
     <gradient
         android:angle="45"
-        android:endColor="?colorSurface"
-        android:startColor="?colorSurfaceVariant" />
-</shape>
\ No newline at end of file
+        android:endColor="@color/defColorSurface"
+        android:startColor="@color/defColorSurfaceVariant" />
+</shape>
diff --git a/app/src/main/res/drawable/bg_divider_rounded_on_primary.xml b/app/src/main/res/drawable/bg_divider_rounded_on_primary.xml
index 783719e7d..a33cc5fee 100644
--- a/app/src/main/res/drawable/bg_divider_rounded_on_primary.xml
+++ b/app/src/main/res/drawable/bg_divider_rounded_on_primary.xml
@@ -3,5 +3,5 @@
     android:shape="rectangle">
     <size android:height="4dp" />
     <corners android:radius="2dp" />
-    <solid android:color="?colorOnPrimary" />
-</shape>
\ No newline at end of file
+    <solid android:color="@color/defColorOnPrimary" />
+</shape>
diff --git a/app/src/main/res/drawable/bg_selectable.xml b/app/src/main/res/drawable/bg_selectable.xml
index c7bb35a7f..b626ec142 100644
--- a/app/src/main/res/drawable/bg_selectable.xml
+++ b/app/src/main/res/drawable/bg_selectable.xml
@@ -3,7 +3,7 @@
     <item android:state_pressed="true">
         <shape android:shape="rectangle">
             <corners android:radius="@dimen/r1" />
-            <solid android:color="?colorPrimaryVariant" />
+            <solid android:color="@color/defColorPrimaryVariant" />
         </shape>
     </item>
     <item>
@@ -11,4 +11,4 @@
             <solid android:color="@android:color/transparent" />
         </shape>
     </item>
-</selector>
\ No newline at end of file
+</selector>
diff --git a/app/src/main/res/drawable/bg_selectable_borderless.xml b/app/src/main/res/drawable/bg_selectable_borderless.xml
index c7bb35a7f..b626ec142 100644
--- a/app/src/main/res/drawable/bg_selectable_borderless.xml
+++ b/app/src/main/res/drawable/bg_selectable_borderless.xml
@@ -3,7 +3,7 @@
     <item android:state_pressed="true">
         <shape android:shape="rectangle">
             <corners android:radius="@dimen/r1" />
-            <solid android:color="?colorPrimaryVariant" />
+            <solid android:color="@color/defColorPrimaryVariant" />
         </shape>
     </item>
     <item>
@@ -11,4 +11,4 @@
             <solid android:color="@android:color/transparent" />
         </shape>
     </item>
-</selector>
\ No newline at end of file
+</selector>
diff --git a/app/src/main/res/drawable/bg_shadow.xml b/app/src/main/res/drawable/bg_shadow.xml
index 4f7bd989b..5d6c86bcf 100644
--- a/app/src/main/res/drawable/bg_shadow.xml
+++ b/app/src/main/res/drawable/bg_shadow.xml
@@ -3,6 +3,6 @@
     android:shape="rectangle">
     <gradient
         android:angle="270"
-        android:endColor="?colorSurfaceVariant"
+        android:endColor="@color/defColorSurfaceVariant"
         android:startColor="@android:color/transparent" />
-</shape>
\ No newline at end of file
+</shape>
diff --git a/app/src/main/res/drawable/fast_scroll_thumb.xml b/app/src/main/res/drawable/fast_scroll_thumb.xml
index 19c3590fa..f0ae9cd31 100644
--- a/app/src/main/res/drawable/fast_scroll_thumb.xml
+++ b/app/src/main/res/drawable/fast_scroll_thumb.xml
@@ -4,14 +4,14 @@
     <item android:state_pressed="true">
         <shape android:shape="rectangle">
             <corners android:radius="@dimen/r1" />
-            <solid android:color="?colorOnSurfaceVariant" />
+            <solid android:color="@color/defColorOnSurfaceVariant" />
             <size android:width="5dp" android:height="5dp" />
         </shape>
     </item>
     <item>
         <shape android:shape="rectangle">
             <corners android:radius="@dimen/r1" />
-            <solid android:color="?colorOnSurfaceVariant" />
+            <solid android:color="@color/defColorOnSurfaceVariant" />
             <size android:width="5dp" android:height="5dp" />
         </shape>
     </item>
diff --git a/app/src/main/res/drawable/progress_determinate.xml b/app/src/main/res/drawable/progress_determinate.xml
index 95b275b5d..c50466498 100644
--- a/app/src/main/res/drawable/progress_determinate.xml
+++ b/app/src/main/res/drawable/progress_determinate.xml
@@ -10,7 +10,7 @@
     <item android:id="@android:id/secondaryProgress">
         <clip>
             <shape>
-                <solid android:color="?colorSecondary" />
+                <solid android:color="@color/defColorSecondary" />
             </shape>
         </clip>
     </item>
@@ -18,9 +18,9 @@
     <item android:id="@android:id/progress">
         <clip>
             <shape>
-                <solid android:color="?colorPrimary" />
+                <solid android:color="@color/defColorPrimary" />
             </shape>
         </clip>
     </item>
 
-</layer-list>
\ No newline at end of file
+</layer-list>
diff --git a/app/src/main/res/values/default_color.xml b/app/src/main/res/values/default_color.xml
new file mode 100644
index 000000000..93203ddd0
--- /dev/null
+++ b/app/src/main/res/values/default_color.xml
@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+    Pre Android 5.0 does not support accessing colors from attributes in drawables
+    These values are from the default theme (Piplup light)
+-->
+<resources>
+    <color name="defColorPrimary">#4EAFF5</color>
+    <color name="defColorPrimaryVariant">#804EAFF5</color>
+    <color name="defColorSecondary">#3E78AF</color>
+    <color name="defColorSecondaryVariant">#803E78AF</color>
+    <color name="defColorSurface">#F9F9F9</color>
+    <color name="defColorSurfaceVariant">#E8E8E8</color>
+    <color name="defColorSurfaceSurfaceVariant">@color/defColorOnSurface</color>
+    <color name="defColorOnPrimary">#F9F9F9</color>
+    <color name="defColorOnPrimaryVariant">#D9E6E6E6</color>
+    <color name="defColorOnSecondary">#F9F9F9</color>
+    <color name="defColorOnBackground">@color/defColorOnSurface</color>
+    <color name="defColorError">#CC0047</color>
+    <color name="defColorOnError">#F9F9F9</color>
+    <color name="defColorOnSurface">#444444</color>
+    <color name="defColorOnSurfaceVariant">#80444444</color>
+    <color name="defColorDisabled">#808080</color>
+    <color name="defColorDisabledVariant">#66808080</color>
+</resources>