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

<resources>

    <style name="GadgetbridgeTheme" parent="Theme.AppCompat.Light.DarkActionBar">
        <item name="textColorPrimary">@color/primarytext_light</item>
        <item name="textColorSecondary">@color/secondarytext</item>
        <item name="textColorTertiary">@color/tertiarytext_light</item>

        <item name="colorPrimary">@color/primary_light</item>
        <item name="colorPrimaryDark">@color/primarydark_light</item>
        <item name="colorAccent">@color/accent</item>

        <item name="android:buttonStyle">@style/Widget.AppCompat.Button.Colored</item>
        <item name="buttonStyle">@style/Widget.AppCompat.Button.Colored</item>

        <item name="chart_deep_sleep">@color/chart_deep_sleep_light</item>
        <item name="chart_light_sleep">@color/chart_light_sleep_light</item>
        <item name="chart_activity">@color/chart_activity_light</item>
        <item name="chart_not_worn">@color/chart_not_worn_light</item>
    </style>

    <style name="GadgetbridgeTheme.NoActionBar">
        <item name="windowActionBar">false</item>
        <item name="windowNoTitle">true</item>
    </style>

    <!-- dark theme -->
    <style name="GadgetbridgeThemeDark" parent="Theme.AppCompat">
        <item name="textColorPrimary">@color/primarytext_dark</item>
        <item name="textColorSecondary">@color/secondarytext</item>
        <item name="textColorTertiary">@color/tertiarytext_dark</item>

        <item name="colorPrimary">@color/primary_dark</item>
        <item name="colorPrimaryDark">@color/primarydark_dark</item>
        <item name="colorAccent">@color/accent</item>

        <item name="android:buttonStyle">@style/ButtonDark</item>
        <item name="buttonStyle">@style/ButtonDark</item>

        <item name="chart_deep_sleep">@color/chart_deep_sleep_dark</item>
        <item name="chart_light_sleep">@color/chart_light_sleep_dark</item>
        <item name="chart_activity">@color/chart_activity_dark</item>
        <item name="chart_not_worn">@color/chart_not_worn_dark</item>
    </style>

    <style name="ButtonDark" parent="Widget.AppCompat.Button.Colored">
        <item name="android:textColor">@color/btn_dark</item>
    </style>

    <style name="GadgetbridgeThemeDark.NoActionBar">
        <item name="windowActionBar">false</item>
        <item name="windowNoTitle">true</item>
    </style>

    <style name="GadgetbridgeTheme.AppBarOverlay" parent="ThemeOverlay.AppCompat.Dark.ActionBar" />

    <style name="GadgetbridgeTheme.PopupOverlay" parent="ThemeOverlay.AppCompat.Light" />
</resources>