Windows phone style updation not working - xaml

Question

I have applied style to textblocks in my windows phone 7.1 app, and this is reflected in VS designer. But when I run it, changes are not visible at all. Code runs without error, except that changes are lost while debugging it, and Background property isn't showing any changes in designer and debugging mode.
<Application
x:Class="PhoneApp1.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone">
<!--Application Resources-->
<Application.Resources>
<Color x:Key="Foreground">Red</Color>
<SolidColorBrush
x:Key="PhoneForegroundBrush"
Color="{StaticResource Foreground}"/>
<Style TargetType="TextBlock" x:Key="PhoneTextNormalStyle">
<Setter Property="FontSize" Value="55"/>
</Style>
</Application.Resources>
<Application.ApplicationLifetimeObjects>
<!--Required object that handles lifetime events for the application-->
<shell:PhoneApplicationService
Launching="Application_Launching" Closing="Application_Closing"
Activated="Application_Activated" Deactivated="Application_Deactivated"/>
</Application.ApplicationLifetimeObjects>
</Application>
<phone:PhoneApplicationPage
x:Class="PhoneApp1.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d" d:DesignWidth="480" d:DesignHeight="768"
Background="{StaticResource PhoneBackgroundBrush}"
FontFamily="{StaticResource PhoneFontFamilyNormal}"
FontSize="{StaticResource PhoneFontSizeNormal}"
Foreground="{StaticResource PhoneForegroundBrush}"
SupportedOrientations="Portrait" Orientation="Portrait"
shell:SystemTray.IsVisible="True">
<!--LayoutRoot is the root grid where all page content is placed-->
<Grid x:Name="LayoutRoot">
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<!--TitlePanel contains the name of the application and page title-->
<StackPanel x:Name="TitlePanel" Grid.Row="0" Margin="12,17,0,28">
<TextBlock x:Name="ApplicationTitle" Text="Guess markets" Style="{StaticResource PhoneTextNormalStyle}"/>
<TextBlock x:Name="PageTitle" Text="Nifty" Margin="9,-7,0,0" Style="{StaticResource PhoneTextNormalStyle}" />
</StackPanel>
<!--ContentPanel - place additional content here-->
<Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
<TextBlock Text="Level"/>
</Grid>
</Grid>
<!--Sample code showing usage of ApplicationBar-->
<!--<phone:PhoneApplicationPage.ApplicationBar>
<shell:ApplicationBar IsVisible="True" IsMenuEnabled="True">
<shell:ApplicationBarIconButton IconUri="/Images/appbar_button1.png" Text="Button 1"/>
<shell:ApplicationBarIconButton IconUri="/Images/appbar_button2.png" Text="Button 2"/>
<shell:ApplicationBar.MenuItems>
<shell:ApplicationBarMenuItem Text="MenuItem 1"/>
<shell:ApplicationBarMenuItem Text="MenuItem 2"/>
</shell:ApplicationBar.MenuItems>
</shell:ApplicationBar>
</phone:PhoneApplicationPage.ApplicationBar>-->
</phone:PhoneApplicationPage>

Answer 1

Try this code within your Application.Resources tag
<Application.Resources>
<Style TargetType="TextBlock" x:Key="PhoneTextNormalStyle">
<Setter Property="FontSize" Value="55"/>
<Setter Property="ForeGround" Value="Black"/>
</Style>
</Application.Resources>
Give a foreground color to the text and see.
There's nothing wrong with which you've posted.
Hope it helps!