wulkanowy-mod/app/src/main/res/values-night/styles.xml

<resources xmlns:tools="http://schemas.android.com/tools">

    <style name="WulkanowyTheme" parent="@style/Theme.MaterialComponents">
        <item name="colorPrimary">@color/colorPrimaryLight</item>
        <item name="colorSecondary">@color/colorPrimaryLight</item>
        <item name="colorError">@color/colorErrorLight</item>
        <item name="colorDivider">@color/colorDividerInverse</item>
        <item name="android:windowBackground">?colorSurface</item>
        <item name="android:textColor">?android:textColorPrimary</item>
        <item name="android:statusBarColor" tools:targetApi="lollipop">@android:color/black</item>
    </style>

    <style name="WulkanowyTheme.Black" parent="WulkanowyTheme.NoActionBar">
        <item name="colorSurface">@android:color/black</item>
    </style>
</resources>