improve:计时器UI

Ink Canvas/Windows/SeewoStyleTimerWindow.xaml

@@ -10,7 +10,7 @@
         Loaded="Window_Loaded" Closing="Window_Closing" WindowStartupLocation="CenterScreen"
         Title="Ink Canvas 画板 - 计时器" Height="450" Width="900">
 
-    <Border Background="{DynamicResource SeewoTimerWindowBackground}" CornerRadius="15" BorderThickness="1" BorderBrush="{DynamicResource SeewoTimerWindowBorderBrush}" Margin="10">
+    <Border Background="{DynamicResource SeewoTimerWindowBackground}" CornerRadius="15" BorderThickness="1" BorderBrush="{DynamicResource SeewoTimerWindowBorderBrush}" Margin="10" x:Name="MainBorder">
         <Grid>
             <!-- 主要内容区域 -->
             <Grid>
@@ -266,7 +266,7 @@
                             
                             <!-- 分割线 -->
                             <Border Width="2" Background="{DynamicResource SeewoTimerWindowButtonForeground}" 
-                                    Opacity="0.5" HorizontalAlignment="Left" VerticalAlignment="Stretch" 
+                                    Opacity="0.3" HorizontalAlignment="Left" VerticalAlignment="Stretch" 
                                     Margin="580,0,0,0"/>
                             
                             <!-- 右侧：快捷选项区域 -->

Ink Canvas/Windows/SeewoStyleTimerWindow.xaml.cs

@@ -129,6 +129,7 @@ namespace Ink_Canvas
                 else if (settings.Appearance.Theme == 1) // 深色主题
                 {
                     iNKORE.UI.WPF.Modern.ThemeManager.SetRequestedTheme(this, iNKORE.UI.WPF.Modern.ElementTheme.Dark);
+                    SetDarkThemeBorder();
                 }
                 else // 跟随系统主题
                 {
@@ -140,6 +141,7 @@ namespace Ink_Canvas
                     else
                     {
                         iNKORE.UI.WPF.Modern.ThemeManager.SetRequestedTheme(this, iNKORE.UI.WPF.Modern.ElementTheme.Dark);
+                        SetDarkThemeBorder();
                     }
                 }
             }
@@ -692,5 +694,20 @@ namespace Ink_Canvas
                 // 如果保存到注册表失败，静默处理
             }
         }
+
+        // 设置深色主题下的灰色边框
+        private void SetDarkThemeBorder()
+        {
+            try
+            {
+                if (MainBorder != null)
+                {
+                    MainBorder.BorderBrush = new SolidColorBrush(Color.FromRgb(64, 64, 64)); 
+                }
+            }
+            catch
+            {
+            }
+        }
     }
 }