simplesshd/app/src/main/res/values/styles.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <style name="tv_button" parent="TextAppearance.Leanback">
	<item name="android:layout_width">fill_parent</item>
	<item name="android:layout_height">1dp</item>
	<item name="android:layout_weight">1</item>
	<item name="android:layout_gravity">center</item>
	<item name="android:textAllCaps">false</item>
	<item name="android:textSize">20sp</item>
	<item name="android:textColor">#ffff</item>
	<item name="android:background">@drawable/tv_button_bg</item>
    </style>
</resources>