fix: enforce deep dark backgrounds on UserControls and inject explicit DataGrid/ComboBox templates to eliminate white backgrounds

Styles/Theme.xaml

@@ -31,11 +31,15 @@
     <FontFamily x:Key="ModernFont">Segoe UI, Apple SD Gothic Neo, Malgun Gothic</FontFamily>
     <FontFamily x:Key="IconFont">Segoe MDL2 Assets, Segoe Fluent Icons</FontFamily>
 
-    <!-- Global System Brushes Override (WPF DataGrid 기본 선택색 덮어쓰기) -->
+    <!-- Global System Brushes Override (WPF DataGrid & Control 기본 시스템 브러시 덮어쓰기) -->
     <SolidColorBrush x:Key="{x:Static SystemColors.HighlightBrushKey}" Color="#2563EB" />
     <SolidColorBrush x:Key="{x:Static SystemColors.HighlightTextBrushKey}" Color="#FFFFFF" />
-    <SolidColorBrush x:Key="{x:Static SystemColors.InactiveSelectionHighlightBrushKey}" Color="#1E3A8A" />
+    <SolidColorBrush x:Key="{x:Static SystemColors.InactiveSelectionHighlightBrushKey}" Color="#1D4ED8" />
     <SolidColorBrush x:Key="{x:Static SystemColors.InactiveSelectionHighlightTextBrushKey}" Color="#FFFFFF" />
+    <SolidColorBrush x:Key="{x:Static SystemColors.WindowBrushKey}" Color="#1E293B" />
+    <SolidColorBrush x:Key="{x:Static SystemColors.WindowTextBrushKey}" Color="#F8FAFC" />
+    <SolidColorBrush x:Key="{x:Static SystemColors.ControlBrushKey}" Color="#0F172A" />
+    <SolidColorBrush x:Key="{x:Static SystemColors.ControlTextBrushKey}" Color="#F8FAFC" />
 
     <!-- Nav Button Style -->
     <Style x:Key="NavButtonStyle" TargetType="RadioButton">
@@ -56,7 +60,6 @@
                             Padding="12,0"
                             Margin="8,2">
                         <Grid>
-                            <!-- Active Accent Indicator -->
                             <Rectangle x:Name="indicator"
                                        Width="3.5"
                                        Height="18"
@@ -201,16 +204,19 @@
     </Style>
 
     <!-- ============================================================================== -->
-    <!-- Modern ComboBox & ComboBoxItem Style (선택칸 고대비 가독성 강화) -->
+    <!-- Custom Modern ComboBox (완전한 Dark 템플릿 - 회색 시스템 버튼 원천 제거) -->
     <!-- ============================================================================== -->
 
-    <Style TargetType="ComboBoxItem">
+    <!-- ComboBoxItem Style -->
+    <Style x:Key="ModernComboBoxItemStyle" TargetType="ComboBoxItem">
         <Setter Property="Background" Value="#1E293B" />
         <Setter Property="Foreground" Value="#F8FAFC" />
-        <Setter Property="Padding" Value="10,8" />
+        <Setter Property="Padding" Value="12,8" />
         <Setter Property="FontSize" Value="13" />
         <Setter Property="FontFamily" Value="{StaticResource ModernFont}" />
         <Setter Property="Cursor" Value="Hand" />
+        <Setter Property="HorizontalContentAlignment" Value="Left" />
+        <Setter Property="VerticalContentAlignment" Value="Center" />
         <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="ComboBoxItem">
@@ -227,7 +233,7 @@
                         <Trigger Property="IsSelected" Value="True">
                             <Setter TargetName="itemBorder" Property="Background" Value="#1D4ED8" />
                             <Setter Property="Foreground" Value="#FFFFFF" />
-                            <Setter Property="FontWeight" Value="SemiBold" />
+                            <Setter Property="FontWeight" Value="Bold" />
                         </Trigger>
                     </ControlTemplate.Triggers>
                 </ControlTemplate>
@@ -235,35 +241,110 @@
         </Setter>
     </Style>
 
+    <!-- ComboBox ToggleButton Template -->
+    <ControlTemplate x:Key="ComboBoxToggleButtonTemplate" TargetType="ToggleButton">
+        <Border x:Name="templateRoot"
+                Background="{TemplateBinding Background}"
+                BorderBrush="{TemplateBinding BorderBrush}"
+                BorderThickness="{TemplateBinding BorderThickness}"
+                CornerRadius="6">
+            <Grid HorizontalAlignment="Right" Width="30">
+                <!-- Dropdown Arrow Icon -->
+                <TextBlock Text="&#xE70D;"
+                           FontFamily="{StaticResource IconFont}"
+                           FontSize="10"
+                           Foreground="{StaticResource TextSecondaryBrush}"
+                           HorizontalAlignment="Center"
+                           VerticalAlignment="Center" />
+            </Grid>
+        </Border>
+        <ControlTemplate.Triggers>
+            <Trigger Property="IsMouseOver" Value="True">
+                <Setter TargetName="templateRoot" Property="BorderBrush" Value="{StaticResource PrimaryAccentBrush}" />
+            </Trigger>
+            <Trigger Property="IsChecked" Value="True">
+                <Setter TargetName="templateRoot" Property="BorderBrush" Value="{StaticResource PrimaryAccentHoverBrush}" />
+            </Trigger>
+        </ControlTemplate.Triggers>
+    </ControlTemplate>
+
+    <!-- ComboBox Main Style -->
     <Style TargetType="ComboBox">
         <Setter Property="Background" Value="#0F172A" />
         <Setter Property="Foreground" Value="#F8FAFC" />
         <Setter Property="BorderBrush" Value="{StaticResource CardBorderBrush}" />
         <Setter Property="BorderThickness" Value="1" />
-        <Setter Property="Padding" Value="8,4" />
+        <Setter Property="Padding" Value="10,6" />
         <Setter Property="FontFamily" Value="{StaticResource ModernFont}" />
         <Setter Property="FontSize" Value="13" />
+        <Setter Property="ItemContainerStyle" Value="{StaticResource ModernComboBoxItemStyle}" />
+        <Setter Property="Template">
+            <Setter.Value>
+                <ControlTemplate TargetType="ComboBox">
+                    <Grid x:Name="templateRoot">
+                        <Popup x:Name="PART_Popup"
+                               AllowsTransparency="True"
+                               IsOpen="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}"
+                               Placement="Bottom"
+                               PopupAnimation="Slide">
+                            <Border x:Name="dropDownBorder"
+                                    Background="#1E293B"
+                                    BorderBrush="#334155"
+                                    BorderThickness="1"
+                                    CornerRadius="6"
+                                    MaxHeight="{TemplateBinding MaxDropDownHeight}"
+                                    MinWidth="{Binding ActualWidth, ElementName=templateRoot}">
+                                <ScrollViewer x:Name="DropDownScrollViewer" Margin="2">
+                                    <ItemsPresenter x:Name="ItemsPresenter" KeyboardNavigation.DirectionalNavigation="Contained" />
+                                </ScrollViewer>
+                            </Border>
+                        </Popup>
+
+                        <!-- Toggle Button (Closed Box) -->
+                        <ToggleButton x:Name="toggleButton"
+                                      Background="{TemplateBinding Background}"
+                                      BorderBrush="{TemplateBinding BorderBrush}"
+                                      BorderThickness="{TemplateBinding BorderThickness}"
+                                      IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}"
+                                      Template="{StaticResource ComboBoxToggleButtonTemplate}" />
+
+                        <!-- Content Area -->
+                        <ContentPresenter x:Name="contentPresenter"
+                                          Content="{TemplateBinding SelectionBoxItem}"
+                                          ContentTemplate="{TemplateBinding SelectionBoxItemTemplate}"
+                                          ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}"
+                                          ContentStringFormat="{TemplateBinding SelectionBoxItemStringFormat}"
+                                          HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
+                                          IsHitTestVisible="False"
+                                          Margin="{TemplateBinding Padding}"
+                                          VerticalAlignment="{TemplateBinding VerticalContentAlignment}" />
+                    </Grid>
+                </ControlTemplate>
+            </Setter.Value>
+        </Setter>
     </Style>
 
     <!-- ============================================================================== -->
-    <!-- Modern DataGrid, ColumnHeader, Row, Cell Styles (그리드 선택칸 고대비 가독성 보장) -->
+    <!-- Modern DataGrid Sub-Styles (ColumnHeader, Row, Cell 완벽 바인딩) -->
     <!-- ============================================================================== -->
 
-    <!-- 1. DataGrid Column Header (어두운 배경 + 밝고 선명한 텍스트) -->
-    <Style TargetType="DataGridColumnHeader">
+    <!-- 1. ColumnHeader Style -->
+    <Style x:Key="ModernColumnHeaderStyle" TargetType="DataGridColumnHeader">
         <Setter Property="Background" Value="#090D16" />
-        <Setter Property="Foreground" Value="#E2E8F0" />
+        <Setter Property="Foreground" Value="#93C5FD" />
         <Setter Property="FontWeight" Value="Bold" />
-        <Setter Property="FontSize" Value="12" />
-        <Setter Property="Padding" Value="12,10" />
+        <Setter Property="FontSize" Value="12.5" />
+        <Setter Property="Padding" Value="14,10" />
         <Setter Property="BorderBrush" Value="#334155" />
         <Setter Property="BorderThickness" Value="0,0,1,1" />
         <Setter Property="HorizontalContentAlignment" Value="Left" />
     </Style>
 
-    <!-- 2. DataGrid Cell (선택 시 텍스트 명확화) -->
-    <Style TargetType="DataGridCell">
-        <Setter Property="Padding" Value="10,8" />
+    <!-- 2. Cell Style -->
+    <Style x:Key="ModernCellStyle" TargetType="DataGridCell">
+        <Setter Property="Background" Value="Transparent" />
+        <Setter Property="Foreground" Value="#F8FAFC" />
+        <Setter Property="Padding" Value="12,8" />
         <Setter Property="BorderThickness" Value="0" />
         <Setter Property="FocusVisualStyle" Value="{x:Null}" />
         <Setter Property="Template">
@@ -279,18 +360,19 @@
             <Trigger Property="IsSelected" Value="True">
                 <Setter Property="Background" Value="#2563EB" />
                 <Setter Property="Foreground" Value="#FFFFFF" />
-                <Setter Property="FontWeight" Value="SemiBold" />
             </Trigger>
         </Style.Triggers>
     </Style>
 
-    <!-- 3. DataGrid Row (호버 및 선택 시 진한 파란색 배경 + 순백색 글자 강제) -->
-    <Style TargetType="DataGridRow">
-        <Setter Property="Background" Value="Transparent" />
+    <!-- 3. Row Style -->
+    <Style x:Key="ModernRowStyle" TargetType="DataGridRow">
+        <Setter Property="Background" Value="#1E293B" />
         <Setter Property="Foreground" Value="#F8FAFC" />
         <Setter Property="FontFamily" Value="{StaticResource ModernFont}" />
         <Setter Property="FontSize" Value="12.5" />
         <Setter Property="Cursor" Value="Hand" />
+        <Setter Property="BorderThickness" Value="0,0,0,1" />
+        <Setter Property="BorderBrush" Value="#2D3748" />
         <Style.Triggers>
             <Trigger Property="IsMouseOver" Value="True">
                 <Setter Property="Background" Value="#1E3A8A" />
@@ -299,14 +381,13 @@
             <Trigger Property="IsSelected" Value="True">
                 <Setter Property="Background" Value="#2563EB" />
                 <Setter Property="Foreground" Value="#FFFFFF" />
-                <Setter Property="FontWeight" Value="SemiBold" />
             </Trigger>
         </Style.Triggers>
     </Style>
 
     <!-- 4. Global Modern DataGrid Style -->
     <Style x:Key="ModernDataGridStyle" TargetType="DataGrid">
-        <Setter Property="Background" Value="{StaticResource CardBgBrush}" />
+        <Setter Property="Background" Value="#1E293B" />
         <Setter Property="BorderBrush" Value="{StaticResource CardBorderBrush}" />
         <Setter Property="BorderThickness" Value="1" />
         <Setter Property="Foreground" Value="#F8FAFC" />
@@ -322,9 +403,18 @@
         <Setter Property="SelectionMode" Value="Single" />
         <Setter Property="FontFamily" Value="{StaticResource ModernFont}" />
         <Setter Property="FontSize" Value="12.5" />
+        <!-- 명시적 서브 스타일 세터 주입 (Windows 기본 흰색 테마 침투 차단) -->
+        <Setter Property="ColumnHeaderStyle" Value="{StaticResource ModernColumnHeaderStyle}" />
+        <Setter Property="RowStyle" Value="{StaticResource ModernRowStyle}" />
+        <Setter Property="CellStyle" Value="{StaticResource ModernCellStyle}" />
     </Style>
 
-    <!-- CheckBox Style for DataGrid Selection -->
+    <!-- Default TargetType Styles for Implicit Binding -->
+    <Style TargetType="DataGridColumnHeader" BasedOn="{StaticResource ModernColumnHeaderStyle}" />
+    <Style TargetType="DataGridCell" BasedOn="{StaticResource ModernCellStyle}" />
+    <Style TargetType="DataGridRow" BasedOn="{StaticResource ModernRowStyle}" />
+
+    <!-- CheckBox Style -->
     <Style TargetType="CheckBox">
         <Setter Property="Foreground" Value="#F8FAFC" />
         <Setter Property="FontSize" Value="13" />
@@ -332,4 +422,21 @@
         <Setter Property="VerticalAlignment" Value="Center" />
     </Style>
 
+    <!-- ListBox & ListBoxItem Style -->
+    <Style TargetType="ListBoxItem">
+        <Setter Property="Background" Value="Transparent" />
+        <Setter Property="Foreground" Value="#F8FAFC" />
+        <Setter Property="Padding" Value="8,4" />
+        <Style.Triggers>
+            <Trigger Property="IsMouseOver" Value="True">
+                <Setter Property="Background" Value="#1E3A8A" />
+                <Setter Property="Foreground" Value="#FFFFFF" />
+            </Trigger>
+            <Trigger Property="IsSelected" Value="True">
+                <Setter Property="Background" Value="#2563EB" />
+                <Setter Property="Foreground" Value="#FFFFFF" />
+            </Trigger>
+        </Style.Triggers>
+    </Style>
+
 </ResourceDictionary>