App.xaml

<Application x:Class="MathMastermind.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:local="clr-namespace:MathMastermind"
             StartupUri="MainWindow.xaml">
    <Application.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <ResourceDictionary Source="Theme/Generic.xaml" />
            </ResourceDictionary.MergedDictionaries>
            <Style x:Key="FocusVisual">
                <Setter Property="Control.Template">
                    <Setter.Value>
                        <ControlTemplate>
                            <Rectangle Margin="2" StrokeDashArray="1 2" Stroke="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}" SnapsToDevicePixels="true" StrokeThickness="1"/>
                        </ControlTemplate>
                    </Setter.Value>
                </Setter>
            </Style>
            <SolidColorBrush x:Key="Button.Static.Background" Color="#FFDDDDDD"/>
            <SolidColorBrush x:Key="Button.Static.Border" Color="#FF707070"/>
            <SolidColorBrush x:Key="Button.MouseOver.Background" Color="#FFBEE6FD"/>
            <SolidColorBrush x:Key="Button.MouseOver.Border" Color="#FF3C7FB1"/>
            <SolidColorBrush x:Key="Button.Pressed.Background" Color="#FFC4E5F6"/>
            <SolidColorBrush x:Key="Button.Pressed.Border" Color="#FF2C628B"/>
            <SolidColorBrush x:Key="Button.Disabled.Background" Color="#FFF4F4F4"/>
            <SolidColorBrush x:Key="Button.Disabled.Border" Color="#FFADB2B5"/>
            <SolidColorBrush x:Key="Button.Disabled.Foreground" Color="#FF838383"/>
            <Style x:Key="TextButton" TargetType="{x:Type Button}">
                <Setter Property="FocusVisualStyle" Value="{StaticResource FocusVisual}"/>
                <Setter Property="Background" Value="{StaticResource Button.Static.Background}"/>
                <Setter Property="BorderBrush" Value="{StaticResource Button.Static.Border}"/>
                <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
                <Setter Property="BorderThickness" Value="1"/>
                <Setter Property="HorizontalContentAlignment" Value="Center"/>
                <Setter Property="VerticalContentAlignment" Value="Center"/>
                <Setter Property="Padding" Value="1"/>
                <Setter Property="Template">
                    <Setter.Value>
                        <ControlTemplate TargetType="{x:Type Button}">
                            <Border x:Name="border" Background="{TemplateBinding Background}" BorderThickness="{TemplateBinding BorderThickness}" SnapsToDevicePixels="true">
                                <ContentPresenter x:Name="contentPresenter" Focusable="False" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
                            </Border>
                        </ControlTemplate>
                    </Setter.Value>
                </Setter>
            </Style>
        </ResourceDictionary>
    </Application.Resources>
</Application>