dragon-iso/src/TeamsISO.App/App.xaml

<Application x:Class="TeamsISO.App.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <Application.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <!--
                    Theme color brushes — DARK by default. ThemeManager.Apply()
                    swaps this entry to Theme.Light.xaml at runtime; the brushes
                    are referenced via DynamicResource from WildDragonTheme.xaml
                    so the visual tree re-resolves without an app restart.
                    The DEFAULT here is dark so the app boots into a
                    deterministic state before ThemeManager runs on startup;
                    if the operator's preference is Light or system app-mode
                    is Light, the dictionary swap happens before MainWindow
                    is shown so there's no visible flash.
                -->
                <ResourceDictionary Source="/Themes/Theme.Dark.xaml"/>
                <ResourceDictionary Source="/Themes/WildDragonTheme.xaml"/>
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </Application.Resources>
</Application>