User39/UP2022Ex/App.xaml

<Application x:Class="UP2022Ex.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:local="clr-namespace:UP2022Ex"
             StartupUri="MainWindow.xaml">
    <Application.Resources>

        <Style TargetType="TextBlock">
            <Style.Setters>
                <Setter Property="FontFamily" Value="Monotype Corsiva"/>
                <Setter Property="FontSize" Value="14"/>
            </Style.Setters>
        </Style>

        <Style TargetType="TextBox">
            <Style.Setters>
                <Setter Property="FontFamily" Value="Monotype Corsiva"/>
            </Style.Setters>
        </Style>

        <Style TargetType="Button">
            <Style.Setters>
                <Setter Property="Background" Value="#46B29D"/>
            </Style.Setters>
        </Style>

    </Application.Resources>
</Application>