grim/app/src/main/res/values/themes.xml

<resources xmlns:tools="http://schemas.android.com/tools">
    <!-- Base application theme. -->
    <style name="Theme.Main" parent="Theme.AppCompat.Light.NoActionBar">
        <item name="colorPrimary">@color/yellow</item>
        <item name="colorOnPrimary">@color/black</item>

        <item name="android:statusBarColor">?attr/colorPrimary</item>
        <item name="android:windowLightStatusBar">true</item>

        <item name="android:navigationBarColor">?attr/colorPrimary</item>
        <item name="android:windowLightNavigationBar">true</item>
    </style>
</resources>