small_sheep_android/app/src/main/res/values/theme_appbar.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <style name="ExpandedTitleTextAppearance" parent="TextAppearance.Widget.AppCompat.Toolbar.Title">
        <item name="android:textSize">18sp</item>
        <item name="android:textColor">@android:color/white</item>
    </style>

    <style name="CollapsedTitleTextAppearance" parent="TextAppearance.Widget.AppCompat.Toolbar.Title">
        <item name="android:textSize">18sp</item>
        <item name="android:textColor">@android:color/black</item>
    </style>
</resources>