diff --git a/src/main/res/layout/layout_main.xml b/src/main/res/layout/layout_main.xml
index fa382e87..74a6db30 100644
--- a/src/main/res/layout/layout_main.xml
+++ b/src/main/res/layout/layout_main.xml
@@ -1,14 +1,15 @@
 <?xml version="1.0" encoding="utf-8"?>
 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
-                xmlns:app="http://schemas.android.com/apk/res-auto"
-                android:layout_width="match_parent" android:layout_height="match_parent">
+                xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools"
+                android:layout_width="match_parent" android:layout_height="match_parent"
+                tools:ignore="UnknownIdInLayout">
     <include layout="@layout/toolbar_light_dark" />
     <fragment android:name="com.github.shadowsocks.ShadowsocksSettings"
               android:id="@android:id/content" android:layout_below="@+id/toolbar"
-              android:layout_width="match_parent" android:layout_height="match_parent" />
+              android:layout_width="match_parent" android:layout_height="match_parent"/>
     <android.support.design.widget.FloatingActionButton android:id="@+id/fab" android:layout_width="wrap_content"
                                                         android:layout_height="wrap_content"
-                                                        app:backgroundTint="@color/material_blue_500"
+                                                        app:backgroundTint="@color/material_green_600"
                                                         android:src="@drawable/ic_cloud_off"
                                                         android:layout_gravity="end|bottom"
                                                         android:layout_alignBottom="@+id/toolbar"
diff --git a/src/main/res/values/colors.xml b/src/main/res/values/colors.xml
index 2ce8dac8..157d3c4a 100644
--- a/src/main/res/values/colors.xml
+++ b/src/main/res/values/colors.xml
@@ -12,7 +12,7 @@
   <color name="md__transparent">#00000000</color>
   <color name="md__defaultBackground">#FF555555</color>
 
-  <color name="material_blue_500">#2196F3</color>
+  <color name="material_green_600">#43A047</color>
   <color name="material_blue_grey_300">#90A4AE</color>
   <color name="material_blue_grey_500">#607D8B</color>
   <color name="material_blue_grey_700">#455A64</color>
diff --git a/src/main/res/values/colors_shadow.xml b/src/main/res/values/colors_shadow.xml
deleted file mode 100644
index 87e9fcf5..00000000
--- a/src/main/res/values/colors_shadow.xml
+++ /dev/null
@@ -1,23 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!-- File created by the Android Action Bar Style Generator
-
-     Copyright (C) 2011 The Android Open Source Project
-     Copyright (C) 2012 readyState Software Ltd
-
-     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.
--->
-
-<resources>
-    <color name="pressed_shadow">#CC33B5E5</color>
-    <color name="title">#EEE</color>
-</resources>