tasks/app/src/main/res/values/theme.xml

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

  <style name="DayNight" parent="Theme.MaterialComponents.Light.NoActionBar" />

  <style name="DayNightDialog" parent="Theme.MaterialComponents.Light.Dialog" />

  <style name="DayNightAlert" parent="ThemeOverlay.MaterialComponents.Dialog.Alert" />

  <style name="TasksBase" parent="DayNight">
    <item name="android:windowBackground">@color/window_background</item>
    <item name="android:colorBackground">@color/content_background</item>
    <item name="windowActionModeOverlay">true</item>
    <item name="android:spinnerItemStyle">@style/SpinnerNoPadding</item>
    <item name="dialogTheme">@style/TasksDialog</item>
    <item name="android:dialogTheme">@style/TasksDialog</item>
    <item name="alertDialogTheme">@style/TasksDialogAlert</item>
    <item name="materialAlertDialogTheme">@style/TasksDialogAlert</item>
    <item name="android:textColorPrimary">@color/text_primary</item>
    <item name="android:textColorSecondary">@color/text_secondary</item>
    <item name="android:textColorTertiary">@color/text_tertiary</item>
    <item name="nnf_toolbarTheme">?attr/overlay_theme</item>
    <item name="nnf_separator_color">@color/nnf_light_separator_color</item>
    <item name="nnf_save_icon_color">?attr/colorAccent</item>
    <item name="nnf_dir_icon_color">?attr/colorAccent</item>
    <item name="card_elevation">2dp</item>
    <item name="horizontal_divider_visibility">2</item> <!-- View.GONE -->
    <item name="mdtp_theme_dark">@bool/is_dark</item>
  </style>

  <style name="Tasks" parent="TasksBase"/>

  <style name="TasksDialogAlert" parent="DayNightAlert">
    <item name="android:textColorPrimary">@color/text_primary</item>
    <item name="android:background">@color/dialog_background</item>
    <item name="buttonBarPositiveButtonStyle">@style/AlertButtonStyle</item>
    <item name="buttonBarNegativeButtonStyle">@style/AlertButtonStyle</item>
    <item name="buttonBarNeutralButtonStyle">@style/AlertButtonStyle</item>
  </style>

  <style name="TasksDialog" parent="DayNightDialog"/>

  <style name="ThemeBlack" parent="Tasks">
    <item name="android:windowBackground">@android:color/black</item>
    <item name="android:colorBackground">@android:color/black</item>
    <item name="horizontal_divider_visibility">0</item> <!-- View.VISIBLE -->
  </style>

  <style name="Wallpaper" parent="Tasks">
    <item name="android:windowBackground">@color/black_38</item>
    <item name="android:colorBackground">@color/black_54</item>
    <item name="android:windowShowWallpaper">true</item>
    <item name="card_elevation">0dp</item>
  </style>

</resources>