<Application xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
                xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"
             x:Class="SilverlightApplication9.App"
             >
    <Application.Resources>
        <Style TargetType="Grid">
            <Setter Property="Background" Value="Blue"></Setter>
        </Style>

    </Application.Resources>
</Application>
