GameOfLife/App.xaml

<Application x:Class="GameOfLife.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             StartupUri="MainWindow.xaml">
    <Application.Resources>
    <SolidColorBrush x:Key="RegularElementBackground">#F6F5FA</SolidColorBrush>
    <SolidColorBrush x:Key="ActiveElementBackground">#B3D2F4</SolidColorBrush>
    <SolidColorBrush x:Key="PressedElementBackground">#67A5E9</SolidColorBrush>
    <SolidColorBrush x:Key="DisabledElementBackground">#F5F5F5</SolidColorBrush>

    <SolidColorBrush x:Key="RegularElementForeground">#442C32</SolidColorBrush>
    <SolidColorBrush x:Key="ActiveElementForeground">#442C32</SolidColorBrush>
    <SolidColorBrush x:Key="PressedElementForeground">#FFFFFF</SolidColorBrush>
    <SolidColorBrush x:Key="DisabledElementForeground">#A29598</SolidColorBrush>

    <SolidColorBrush x:Key="RegularElementBorderBrush">#B7B4D6</SolidColorBrush>
    <SolidColorBrush x:Key="ActiveElementBorderBrush">#67A5E9</SolidColorBrush>
    <SolidColorBrush x:Key="PressedElementBorderBrush">#67A5E9</SolidColorBrush>
    <SolidColorBrush x:Key="DisabledElementBorderBrush">#CCCCCC</SolidColorBrush>
      
    <Style x:Key="FlatButton" TargetType="ButtonBase">
      <Setter Property="SnapsToDevicePixels" Value="True"/>
      <Setter Property="Template">
        <Setter.Value>
          <ControlTemplate TargetType="{x:Type ButtonBase}">
            <Border x:Name="Border" Padding="{TemplateBinding Padding}" Background="{StaticResource RegularElementBackground}"
                  BorderThickness="{TemplateBinding BorderThickness}"
                  BorderBrush="{StaticResource RegularElementBorderBrush}">
              <ContentPresenter x:Name="Content"
                              HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
                              VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
            </Border>
            <ControlTemplate.Triggers>
              <Trigger Property="IsEnabled" Value="False">
                <Setter TargetName="Border" Property="Background" Value="{StaticResource DisabledElementBackground}"/>
                <Setter TargetName="Border" Property="BorderBrush" Value="{StaticResource DisabledElementBorderBrush}"/>
                <Setter Property="Foreground" Value="{StaticResource DisabledElementForeground}"/>
              </Trigger>
              <Trigger Property="IsMouseOver" Value="True">
                <Setter TargetName="Border" Property="Background" Value="{StaticResource ActiveElementBackground}"/>
                <Setter TargetName="Border" Property="BorderBrush" Value="{StaticResource ActiveElementBorderBrush}"/>
                <Setter Property="Foreground" Value="{StaticResource ActiveElementForeground}"/>
              </Trigger>
              <Trigger Property="IsFocused" Value="True">
                <Setter TargetName="Border" Property="Background" Value="{StaticResource ActiveElementBackground}"/>
                <Setter TargetName="Border" Property="BorderBrush" Value="{StaticResource ActiveElementBorderBrush}"/>
                <Setter Property="Foreground" Value="{StaticResource ActiveElementForeground}"/>
              </Trigger>
              <Trigger Property="IsPressed" Value="True">
                <Setter TargetName="Border" Property="Background" Value="{StaticResource PressedElementBackground}"/>
                <Setter TargetName="Border" Property="BorderBrush" Value="{StaticResource PressedElementBorderBrush}"/>
                <Setter Property="Foreground" Value="{StaticResource PressedElementForeground}"/>
              </Trigger>
            </ControlTemplate.Triggers>
          </ControlTemplate>
        </Setter.Value>
      </Setter>
      <Setter Property="Foreground" Value="{StaticResource RegularElementForeground}"/>
    </Style>
  </Application.Resources>
</Application>