ConcertAfisha/App.xaml

<Application x:Class="MusicSmth.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:local="clr-namespace:MusicSmth"
             StartupUri="MainWindow.xaml">
    <Application.Resources>
        <Style TargetType="Button" x:Key="ButtonDefault">
            <Setter Property="Foreground" Value="White"/>
            <Setter Property="Background" Value="#0000"/>
            <Setter Property="BorderBrush" Value="#0000"/>
        </Style>
        <Style TargetType="Border" x:Key="BorderDefault">
            <Setter Property="Background" Value="Black"/>
            <Setter Property="CornerRadius" Value="10"/>
        </Style>
        <Style TargetType="DataGridColumnHeader" x:Key="HeadDefault">
            <Setter Property="Foreground" Value="White"/>
            <Setter Property="Background" Value="Black"/>
            <Setter Property="FontWeight" Value="Bold"/>
        </Style>
        <Style TargetType="Border" x:Key="BorderInput">
            <Setter Property="BorderThickness" Value="1"/>
            <Setter Property="CornerRadius" Value="10"/>
            <Setter Property="BorderBrush" Value="Black"/>
        </Style>
        <Style TargetType="TextBox" x:Key="InputDefault">
            <Setter Property="Background" Value="#0000"/>
            <Setter Property="BorderBrush" Value="#0000"/>
        </Style>
    </Application.Resources>
</Application>