App.xaml

<Application x:Class="DateTimeFormatting.App"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:syncfusion="http://schemas.syncfusion.com/wpf"
    StartupUri="Window1.xaml" >
    <Application.Resources>

        <ResourceDictionary>


            <LinearGradientBrush x:Key="ButtonNormalBackground" EndPoint="0,1" StartPoint="0,0">
                <GradientStop Color="#F3F3F3" Offset="0"/>
                <GradientStop Color="#EBEBEB" Offset="0.5"/>
                <GradientStop Color="#DDDDDD" Offset="0.5"/>
                <GradientStop Color="#CDCDCD" Offset="1"/>
            </LinearGradientBrush>
            <SolidColorBrush x:Key="ButtonNormalBorder" Color="#FF707070"/>
            <Style x:Key="ToggleButtonStyle1" TargetType="{x:Type ToggleButton}">
                <Setter Property="Background" Value="{StaticResource ButtonNormalBackground}"/>
                <Setter Property="BorderBrush" Value="{StaticResource ButtonNormalBorder}"/>
                <Setter Property="BorderThickness" Value="1"/>
                <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
                <Setter Property="HorizontalContentAlignment" Value="Center"/>
                <Setter Property="VerticalContentAlignment" Value="Center"/>
                <Setter Property="Cursor" Value="Hand"/>
                <Setter Property="Padding" Value="1"/>
                <Setter Property="Template">
                    <Setter.Value>
                        <ControlTemplate TargetType="{x:Type ToggleButton}">
                            <Grid>
                                <Image Source="/Images/open.png" x:Name="img">
                                    <Image.Effect>
                                        <DropShadowEffect ShadowDepth="0" BlurRadius="1" Opacity="0.3"/>
                                    </Image.Effect>
                                </Image>
                            </Grid>
                            <ControlTemplate.Triggers>
                                <Trigger Property="IsMouseOver" Value="True">
                                    <Setter Property="Effect" TargetName="img">
                                        <Setter.Value>
                                            <DropShadowEffect ShadowDepth="0" BlurRadius="1" Opacity="0.6"/>
                                        </Setter.Value>
                                    </Setter>
                                </Trigger>
                                <Trigger Property="IsChecked" Value="True">
                                    <Setter Property="Source" TargetName="img" Value="/Images/close.png"/>
                                    <Setter Property="ToolTip" Value="ReadOnly"></Setter>
                                    <Setter Property="Effect" TargetName="img">
                                        <Setter.Value>
                                            <syncfusion:DisableEffect/>
                                        </Setter.Value>
                                    </Setter>
                                </Trigger>
                                <Trigger Property="IsChecked" Value="False">
                                    <Setter Property="ToolTip" Value="Edit"></Setter>
                                </Trigger>
                            </ControlTemplate.Triggers>
                        </ControlTemplate>
                    </Setter.Value>
                </Setter>
            </Style>
        </ResourceDictionary>
    </Application.Resources>
</Application>