Various changes to layouts, styles, strings and drawables

app/src/main/res/layout/activity_main.xml

@@ -1,9 +1,9 @@
 <?xml version="1.0" encoding="utf-8"?>
 <androidx.fragment.app.FragmentContainerView xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
-    android:id="@+id/navigation_host"
+    android:id="@+id/nav_host"
     android:name="androidx.navigation.fragment.NavHostFragment"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     app:defaultNavHost="true"
-    app:navGraph="@navigation/navigation_graph" />
+    app:navGraph="@navigation/nav_graph" />