diff --git a/Ink Canvas/Controls/Popups/BackgroundPalettePopupContent.xaml b/Ink Canvas/Controls/Popups/BackgroundPalettePopupContent.xaml
index cb66224f..3d903a98 100644
--- a/Ink Canvas/Controls/Popups/BackgroundPalettePopupContent.xaml	
+++ b/Ink Canvas/Controls/Popups/BackgroundPalettePopupContent.xaml	
@@ -15,22 +15,33 @@
                            Foreground="{DynamicResource TextForeground}"
                            FontSize="10" FontWeight="Bold"
                            HorizontalAlignment="Center"/>
-                <ikw:SimpleStackPanel Orientation="Horizontal" HorizontalAlignment="Center" Spacing="20">
+                <ikw:SimpleStackPanel Orientation="Horizontal" HorizontalAlignment="Center" Spacing="10">
                     <Border x:Name="WhiteboardModeBtn"
-                            Width="60" Height="30"
+                            Width="50" Height="30"
                             Background="#2563eb"
                             CornerRadius="4">
-                        <TextBlock Text="白板" FontSize="10"
+                        <TextBlock Text="白板" FontSize="9"
                                    Foreground="White"
                                    HorizontalAlignment="Center"
                                    VerticalAlignment="Center" />
                     </Border>
                     <Border x:Name="BlackboardModeBtn"
-                            Width="60" Height="30"
-                            Background="LightGray"
+                            Width="50" Height="30"
+                            Background="#162924"
                             CornerRadius="4">
                         <TextBlock Text="黑板"
-                                   Foreground="Black"
+                                   Foreground="White"
+                                   FontSize="9"
+                                   HorizontalAlignment="Center"
+                                   VerticalAlignment="Center" />
+                    </Border>
+                    <Border x:Name="BlackModeBtn"
+                            Width="50" Height="30"
+                            Background="Black"
+                            CornerRadius="4">
+                        <TextBlock Text="纯黑"
+                                   Foreground="White"
+                                   FontSize="9"
                                    HorizontalAlignment="Center"
                                    VerticalAlignment="Center" />
                     </Border>
diff --git a/Ink Canvas/MainWindow.xaml.cs b/Ink Canvas/MainWindow.xaml.cs
index b4892f97..e1833a5b 100644
--- a/Ink Canvas/MainWindow.xaml.cs	
+++ b/Ink Canvas/MainWindow.xaml.cs	
@@ -175,6 +175,7 @@ private void WireUpBackgroundPaletteEvents()
             var content = BackgroundPalettePopupContent;
             content.WhiteboardBtn.MouseUp += WhiteboardModeBtn_MouseUp;
             content.BlackboardBtn.MouseUp += BlackboardModeBtn_MouseUp;
+            content.BlackModeBtn.MouseUp += BlackModeBtn_MouseUp;
             content.RSlider.ValueChanged += BackgroundRSlider_ValueChanged;
             content.GSlider.ValueChanged += BackgroundGSlider_ValueChanged;
             content.BSlider.ValueChanged += BackgroundBSlider_ValueChanged;
diff --git a/Ink Canvas/MainWindow_cs/MW_BoardIcons.cs b/Ink Canvas/MainWindow_cs/MW_BoardIcons.cs
index e3f0ced9..03fd0f17 100644
--- a/Ink Canvas/MainWindow_cs/MW_BoardIcons.cs	
+++ b/Ink Canvas/MainWindow_cs/MW_BoardIcons.cs	
@@ -23,21 +23,26 @@ public partial class MainWindow : Ink_Canvas.Helpers.PerformanceTransparentWin
         /// - 处理白板/黑板模式切换
         /// - 更新背景颜色和墨迹颜色
         /// </remarks>
+        private int currentBackgroundMode = 0; // 0: 白板, 1: 黑板(深绿), 2: 纯黑
+
         private void BoardChangeBackgroundColorBtn_MouseUp(object sender, RoutedEventArgs e)
         {
             if (!isLoaded) return;
 
-            if (BackgroundPalette.IsOpen)
-            {
-                AnimationsHelper.HidePopupWithSlideAndFade(BackgroundPalette);
-            }
-            else
+            // 循环切换背景模式
+            currentBackgroundMode = (currentBackgroundMode + 1) % 3;
+
+            switch (currentBackgroundMode)
             {
-                HideSubPanels();
-                LoadCustomBackgroundColor();
-                UpdateBackgroundButtonsState();
-                AnimationsHelper.ShowPopupWithSlideAndFade(BackgroundPalette);
-                _popupManager?.BringToFront(BackgroundPalette);
+                case 0: // 白板
+                    WhiteboardModeBtn_MouseUp(sender, null);
+                    break;
+                case 1: // 黑板(深绿)
+                    BlackboardModeBtn_MouseUp(sender, null);
+                    break;
+                case 2: // 纯黑
+                    BlackModeBtn_MouseUp(sender, null);
+                    break;
             }
         }
 
@@ -91,6 +96,31 @@ private void BlackboardModeBtn_MouseUp(object sender, MouseButtonEventArgs e)
             UpdateBackgroundButtonsState();
         }
 
+        private void BlackModeBtn_MouseUp(object sender, MouseButtonEventArgs e)
+        {
+            Settings.Canvas.UsingWhiteboard = false;
+            SaveSettingsToFile();
+            ICCWaterMarkWhite.Visibility = Visibility.Visible;
+            ICCWaterMarkDark.Visibility = Visibility.Collapsed;
+
+            Color defaultBlackColor = Color.FromRgb(0, 0, 0);
+
+            if (currentMode == 1)
+            {
+                GridBackgroundCover.Background = new SolidColorBrush(defaultBlackColor);
+                UpdateRGBSliders(defaultBlackColor);
+                CustomBackgroundColor = defaultBlackColor;
+                string colorHex = $"#{defaultBlackColor.R:X2}{defaultBlackColor.G:X2}{defaultBlackColor.B:X2}";
+                Settings.Canvas.CustomBackgroundColor = colorHex;
+                SaveSettingsToFile();
+            }
+
+            CheckLastColor(5);
+            forceEraser = false;
+            CheckColorTheme(true);
+            UpdateBackgroundButtonsState();
+        }
+
         private void BackgroundRSlider_ValueChanged(object sender, RoutedPropertyChangedEventArgs<double> e)
         {
             if (BackgroundRValue != null)