<!-- FocusVisual -->
<Style x:Key="ButtonFocusVisual">
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<Border>
<Rectangle Margin="2"
StrokeThickness="1"
Stroke="#60000000"
StrokeDashArray="1 2" />
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<!-- Button -->
<Style TargetType="Button">
<Setter Property="SnapsToDevicePixels"
Value="true" />
<Setter Property="OverridesDefaultStyle"
Value="true" />
<Setter Property="FocusVisualStyle"
Value="{StaticResource ButtonFocusVisual}" />
<Setter Property="MinHeight"
Value="23" />
<Setter Property="MinWidth"
Value="75" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Border TextBlock.Foreground="{TemplateBinding Foreground}"
x:Name="Border"
CornerRadius="2"
BorderThickness="1">
<Border.BorderBrush>
<LinearGradientBrush StartPoint="0,0"
EndPoint="0,1">
<LinearGradientBrush.GradientStops>
<GradientStopCollection>
<GradientStop Color="{DynamicResource BorderLightColor}"
Offset="0.0" />
<GradientStop Color="{DynamicResource BorderDarkColor}"
Offset="1.0" />
</GradientStopCollection>
</LinearGradientBrush.GradientStops>
</LinearGradientBrush>
</Border.BorderBrush>
<Border.Background>
<LinearGradientBrush EndPoint="0.5,1"
StartPoint="0.5,0">
<GradientStop Color="{DynamicResource ControlLightColor}"
Offset="0" />
<GradientStop Color="{DynamicResource ControlMediumColor}"
Offset="1" />
</LinearGradientBrush>
</Border.Background>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualStateGroup.Transitions>
<VisualTransition GeneratedDuration="0:0:0.5" />
<VisualTransition GeneratedDuration="0"
To="Pressed" />
</VisualStateGroup.Transitions>
<VisualState x:Name="Normal" />
<VisualState x:Name="MouseOver">
<Storyboard>
<ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Panel.Background).
(GradientBrush.GradientStops)[1].(GradientStop.Color)"
Storyboard.TargetName="Border">
<EasingColorKeyFrame KeyTime="0"
Value="{StaticResource ControlMouseOverColor}" />
</ColorAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Pressed">
<Storyboard>
<ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Panel.Background).
(GradientBrush.GradientStops)[1].(GradientStop.Color)"
Storyboard.TargetName="Border">
<EasingColorKeyFrame KeyTime="0"
Value="{StaticResource ControlPressedColor}" />
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Border.BorderBrush).
(GradientBrush.GradientStops)[0].(GradientStop.Color)"
Storyboard.TargetName="Border">
<EasingColorKeyFrame KeyTime="0"
Value="{StaticResource PressedBorderDarkColor}" />
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Border.BorderBrush).
(GradientBrush.GradientStops)[1].(GradientStop.Color)"
Storyboard.TargetName="Border">
<EasingColorKeyFrame KeyTime="0"
Value="{StaticResource PressedBorderLightColor}" />
</ColorAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Panel.Background).
(GradientBrush.GradientStops)[1].(GradientStop.Color)"
Storyboard.TargetName="Border">
<EasingColorKeyFrame KeyTime="0"
Value="{StaticResource DisabledControlDarkColor}" />
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames
Storyboard.TargetProperty="(TextBlock.Foreground).(SolidColorBrush.Color)"
Storyboard.TargetName="Border">
<EasingColorKeyFrame KeyTime="0"
Value="{StaticResource DisabledForegroundColor}" />
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Border.BorderBrush).
(GradientBrush.GradientStops)[1].(GradientStop.Color)"
Storyboard.TargetName="Border">
<EasingColorKeyFrame KeyTime="0"
Value="{StaticResource DisabledBorderDarkColor}" />
</ColorAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<ContentPresenter Margin="2"
HorizontalAlignment="Center"
VerticalAlignment="Center"
RecognizesAccessKey="True" />
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsDefault"
Value="true">
<Setter TargetName="Border"
Property="BorderBrush">
<Setter.Value>
<LinearGradientBrush StartPoint="0,0"
EndPoint="0,1">
<GradientBrush.GradientStops>
<GradientStopCollection>
<GradientStop Color="{DynamicResource DefaultBorderBrushLightBrush}"
Offset="0.0" />
<GradientStop Color="{DynamicResource DefaultBorderBrushDarkColor}"
Offset="1.0" />
</GradientStopCollection>
</GradientBrush.GradientStops>
</LinearGradientBrush>
</Setter.Value>
</Setter>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
Referring from:http://msdn.microsoft.com/en-us/library/ms753328.aspx