ShabaninModulekz/modulekz/App.xaml

<Application x:Class="modulekz.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:local="clr-namespace:modulekz"
             StartupUri="MainWindow.xaml">
    <Application.Resources>
        <Style TargetType="Button" >
            <Setter Property="Background" Value="#4ee9a2"/>
        </Style>
        <Style TargetType="TextBlock">
            <Setter Property ="FontFamily" Value="Calibri"/>
        </Style>
        <Style TargetType="ListBox">
            <Setter Property="Background" Value="#39f9"/>
        </Style>
    </Application.Resources>
</Application>