feat: 优化代码

app/src/main/res/drawable/bg_shadow_bottom_night.xml

@@ -2,7 +2,7 @@
 <shape xmlns:android="http://schemas.android.com/apk/res/android">
     <!--实现应用背景颜色渐变-->
     <gradient
-        android:startColor="#17FFFFFF"
+        android:startColor="#17303030"
         android:endColor="#00FFFFFF"
         android:angle="90" />
 </shape>

app/src/main/res/drawable/ic_launcher_background.xml

@@ -1,8 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <shape xmlns:android="http://schemas.android.com/apk/res/android">
-    <!--实现应用背景颜色渐变-->
+    <solid android:color="@color/md_grey_100" />
-    <gradient
-        android:startColor="#F5F5F5"
-        android:endColor="#ECECEC"
-        android:angle="90" />
 </shape>