Fix: consistent check/revert order + enable accept buttons

All three element sections (webcam border, countdown, web URI) now use
consistent [✕][✓] button order. Green check buttons enabled with click
handlers that save current values as snapshot baseline — revert undoes
to last accepted state, not initial selection.

Countdown section buttons were swapped (had [✓][✕], now [✕][✓]).
Webcam and web sections already had correct visual order.

1e of 7-issue polish batch. 207 tests, 0 warnings.

MainWindow.xaml

@@ -407,7 +407,8 @@
                                 <TextBlock Text="Border Thickness" Foreground="#a0a0b0" FontSize="11" Margin="0,0,0,2"/>
                                 <DockPanel Margin="0,0,0,6">
                                     <Button DockPanel.Dock="Right" Style="{StaticResource IconButton}"
-                                            IsEnabled="False" Width="22" Height="22" Margin="4,0,0,0">
+                                            Width="22" Height="22" Margin="4,0,0,0"
+                                            Click="WebcamBorderAccept_Click">
                                         <Path Data="M4,9 L8,14 L16,4" Stroke="#22c55e" StrokeThickness="2"
                                               Width="14" Height="14" Stretch="Uniform"/>
                                     </Button>
@@ -430,14 +431,15 @@
                                 <TextBlock Text="Timer (minutes)" Foreground="#a0a0b0" FontSize="11" Margin="0,0,0,2"/>
                                 <DockPanel Margin="0,0,0,6">
                                     <Button DockPanel.Dock="Right" Style="{StaticResource IconButton}"
-                                            Width="22" Height="22" ToolTip="Revert"
+                                            Width="22" Height="22" Margin="4,0,0,0"
-                                            Click="CountdownRevert_Click" Margin="4,0,0,0">
+                                            Click="CountdownAccept_Click">
-                                        <Path Data="M5,5 L15,15 M15,5 L5,15" Stroke="#e94560" StrokeThickness="2"
+                                        <Path Data="M4,9 L8,14 L16,4" Stroke="#22c55e" StrokeThickness="2"
                                               Width="14" Height="14" Stretch="Uniform"/>
                                     </Button>
                                     <Button DockPanel.Dock="Right" Style="{StaticResource IconButton}"
-                                            IsEnabled="False" Width="22" Height="22" Margin="4,0,0,0">
+                                            Width="22" Height="22" ToolTip="Revert"
-                                        <Path Data="M4,9 L8,14 L16,4" Stroke="#22c55e" StrokeThickness="2"
+                                            Click="CountdownRevert_Click" Margin="4,0,0,0">
+                                        <Path Data="M5,5 L15,15 M15,5 L5,15" Stroke="#e94560" StrokeThickness="2"
                                               Width="14" Height="14" Stretch="Uniform"/>
                                     </Button>
                                     <Slider DockPanel.Dock="Left" Width="120" Minimum="1" Maximum="60"
@@ -453,7 +455,8 @@
                                 <TextBlock Text="URI" Foreground="#a0a0b0" FontSize="11" Margin="0,0,0,2"/>
                                 <DockPanel>
                                     <Button DockPanel.Dock="Right" Style="{StaticResource IconButton}"
-                                            IsEnabled="False" Width="22" Height="22" Margin="4,0,0,0">
+                                            Width="22" Height="22" Margin="4,0,0,0"
+                                            Click="WebAccept_Click">
                                         <Path Data="M4,9 L8,14 L16,4" Stroke="#22c55e" StrokeThickness="2"
                                               Width="14" Height="14" Stretch="Uniform"/>
                                     </Button>

MainWindow.xaml.cs

@@ -572,15 +572,36 @@ public partial class MainWindow : Window
         }
     }
 
+    private void WebcamBorderAccept_Click(object sender, RoutedEventArgs e)
+    {
+        if (_snapshotElement is Models.Source src)
+        {
+            _snapshotBorderColor = src.BorderColor;
+            _snapshotBorderWidth = src.BorderWidth;
+        }
+    }
+
     private void CountdownRevert_Click(object sender, RoutedEventArgs e)
     {
         if (_snapshotElement is Models.Source src)
             src.TimerMinutes = _snapshotTimerMinutes;
     }
 
+    private void CountdownAccept_Click(object sender, RoutedEventArgs e)
+    {
+        if (_snapshotElement is Models.Source src)
+            _snapshotTimerMinutes = src.TimerMinutes;
+    }
+
     private void WebRevert_Click(object sender, RoutedEventArgs e)
     {
         if (_snapshotElement is Models.Source src)
             src.WebUri = _snapshotWebUri;
     }
+
+    private void WebAccept_Click(object sender, RoutedEventArgs e)
+    {
+        if (_snapshotElement is Models.Source src)
+            _snapshotWebUri = src.WebUri;
+    }
 }

TASKS.md

@@ -828,6 +828,7 @@ No changes to `MusicPlayer`, the 0.20 cap, the ducker, or the meter zones. Build
 11. ✅ Elements scrollbar deselect fix — clicking the Elements panel scrollbar no longer deselects the selected element (scrollbar lives inside the ScrollViewer, not the StackPanel; guard now checks `ElementsScrollViewer` instead of `ElementsPanel`)
 12. ✅ Web source URI + buttons inline — merged URI TextBox and check/revert buttons into a single DockPanel row (✓ rightmost, ✕ left); buttons no longer wrap to a separate line
 13. ✅ Web source URI hidden for webcam — URI section was showing for webcam due to WPF binding path `SelectedElement.Type` not resolving on `WebcamSceneConfig`; replaced with `IsWebSource` virtual property on `SceneElement` (mirrors existing `IsWebcam` pattern), overridden in `Source` to return `Type == SourceType.WebSource`, bound via `BoolToVis`
+14. ✅ Check/revert consistent order + accept — all three element sections (webcam border, countdown timer, web URI) now use consistent [✕][✓] button order; green check buttons enabled with click handlers that save current values as snapshot baseline (so revert undoes to last accepted state, not initial selection)
 
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