You can't use attrs on <L in drawables

Clover/app/src/main/res/drawable/background_accent_rounded.xml

@@ -16,6 +16,6 @@ You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 -->
 <shape xmlns:android="http://schemas.android.com/apk/res/android">
-    <solid android:color="?attr/colorAccent" />
+    <solid android:color="@color/accent" />
     <corners android:radius="2dp" />
 </shape>

Clover/app/src/main/res/drawable/background_hint_arrow.xml

@@ -25,7 +25,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
             <shape
                 android:shape="rectangle">
                 <solid
-                    android:color="?attr/colorAccent" />
+                    android:color="@color/accent" />
             </shape>
         </rotate>
     </item>

Clover/app/src/main/res/values/styles.xml

@@ -16,13 +16,13 @@ You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 -->
 <resources>
-    <!--<color name="primary">#ff4caf50</color>-->
+    <color name="primary">#ff4caf50</color>
-    <!--<color name="primary_dark">#ff388e3c</color>-->
+    <color name="primary_dark">#ff388e3c</color>
-    <!--<color name="accent">#ff009688</color>-->
+    <color name="accent">#ff009688</color>
 
     <!-- Main light theme -->
     <style name="Chan.Theme" parent="Theme.AppCompat.Light.NoActionBar">
-        <!--<item name="colorAccent">#ff009688</item>-->
+        <item name="colorAccent">#ff009688</item>
 
         <item name="android:windowBackground">@android:color/white</item>
         <item name="windowActionModeOverlay">true</item>