diff --git a/app/src/main/res/drawable/ic_half_day_1_24dp.xml b/app/src/main/res/drawable/ic_half_day_1_24dp.xml
deleted file mode 100644
index a17524b..0000000
--- a/app/src/main/res/drawable/ic_half_day_1_24dp.xml
+++ /dev/null
@@ -1,25 +0,0 @@
-<!--
-  ~ Copyright (C) 2016 Phillip Hsu
-  ~
-  ~ Licensed under the Apache License, Version 2.0 (the "License");
-  ~ you may not use this file except in compliance with the License.
-  ~ You may obtain a copy of the License at
-  ~
-  ~      http://www.apache.org/licenses/LICENSE-2.0
-  ~
-  ~ Unless required by applicable law or agreed to in writing, software
-  ~ distributed under the License is distributed on an "AS IS" BASIS,
-  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-  ~ See the License for the specific language governing permissions and
-  ~ limitations under the License.
-  -->
-
-<vector xmlns:android="http://schemas.android.com/apk/res/android"
-        android:width="24dp"
-        android:height="24dp"
-        android:viewportWidth="24.0"
-        android:viewportHeight="24.0">
-    <path
-        android:fillColor="#8a000000"
-        android:pathData="M20,15.31L23.31,12 20,8.69V4h-4.69L12,0.69 8.69,4H4v4.69L0.69,12 4,15.31V20h4.69L12,23.31 15.31,20H20v-4.69zM12,18V6c3.31,0 6,2.69 6,6s-2.69,6 -6,6z"/>
-</vector>
diff --git a/app/src/main/res/drawable/ic_half_day_1_dark_24dp.xml b/app/src/main/res/drawable/ic_half_day_1_dark_24dp.xml
deleted file mode 100644
index 43ae1a3..0000000
--- a/app/src/main/res/drawable/ic_half_day_1_dark_24dp.xml
+++ /dev/null
@@ -1,25 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!--
-  ~ Copyright (C) 2016 Phillip Hsu
-  ~
-  ~ Licensed under the Apache License, Version 2.0 (the "License");
-  ~ you may not use this file except in compliance with the License.
-  ~ You may obtain a copy of the License at
-  ~
-  ~      http://www.apache.org/licenses/LICENSE-2.0
-  ~
-  ~ Unless required by applicable law or agreed to in writing, software
-  ~ distributed under the License is distributed on an "AS IS" BASIS,
-  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-  ~ See the License for the specific language governing permissions and
-  ~ limitations under the License.
-  -->
-
-<!-- http://stackoverflow.com/a/8716798/5055032 -->
-<rotate xmlns:android="http://schemas.android.com/apk/res/android"
-    android:fromDegrees="180"
-    android:toDegrees="180"
-    android:pivotX="50%"
-    android:pivotY="50%"
-    android:drawable="@drawable/ic_half_day_2_dark_24dp">
-</rotate>
\ No newline at end of file
diff --git a/app/src/main/res/drawable/ic_half_day_2_24dp.xml b/app/src/main/res/drawable/ic_half_day_2_24dp.xml
deleted file mode 100644
index 12fb230..0000000
--- a/app/src/main/res/drawable/ic_half_day_2_24dp.xml
+++ /dev/null
@@ -1,25 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!--
-  ~ Copyright (C) 2016 Phillip Hsu
-  ~
-  ~ Licensed under the Apache License, Version 2.0 (the "License");
-  ~ you may not use this file except in compliance with the License.
-  ~ You may obtain a copy of the License at
-  ~
-  ~      http://www.apache.org/licenses/LICENSE-2.0
-  ~
-  ~ Unless required by applicable law or agreed to in writing, software
-  ~ distributed under the License is distributed on an "AS IS" BASIS,
-  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-  ~ See the License for the specific language governing permissions and
-  ~ limitations under the License.
-  -->
-
-<!-- http://stackoverflow.com/a/8716798/5055032 -->
-<rotate xmlns:android="http://schemas.android.com/apk/res/android"
-    android:fromDegrees="180"
-    android:toDegrees="180"
-    android:pivotX="50%"
-    android:pivotY="50%"
-    android:drawable="@drawable/ic_half_day_1_24dp">
-</rotate>
\ No newline at end of file
diff --git a/app/src/main/res/drawable/ic_half_day_2_dark_24dp.xml b/app/src/main/res/drawable/ic_half_day_2_dark_24dp.xml
deleted file mode 100644
index ebbbba0..0000000
--- a/app/src/main/res/drawable/ic_half_day_2_dark_24dp.xml
+++ /dev/null
@@ -1,25 +0,0 @@
-<!--
-  ~ Copyright (C) 2016 Phillip Hsu
-  ~
-  ~ Licensed under the Apache License, Version 2.0 (the "License");
-  ~ you may not use this file except in compliance with the License.
-  ~ You may obtain a copy of the License at
-  ~
-  ~      http://www.apache.org/licenses/LICENSE-2.0
-  ~
-  ~ Unless required by applicable law or agreed to in writing, software
-  ~ distributed under the License is distributed on an "AS IS" BASIS,
-  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-  ~ See the License for the specific language governing permissions and
-  ~ limitations under the License.
-  -->
-
-<vector xmlns:android="http://schemas.android.com/apk/res/android"
-        android:width="24dp"
-        android:height="24dp"
-        android:viewportWidth="24.0"
-        android:viewportHeight="24.0">
-    <path
-        android:fillColor="#FFFFFF"
-        android:pathData="M20,15.31L23.31,12 20,8.69V4h-4.69L12,0.69 8.69,4H4v4.69L0.69,12 4,15.31V20h4.69L12,23.31 15.31,20H20v-4.69zM12,18V6c3.31,0 6,2.69 6,6s-2.69,6 -6,6z"/>
-</vector>