diff --git a/Controls/LeftPanel.xaml b/Controls/LeftPanel.xaml
index c4047d9..2019db4 100644
--- a/Controls/LeftPanel.xaml
+++ b/Controls/LeftPanel.xaml
@@ -155,12 +155,11 @@
                                     </TextBlock>
 
                                     <TextBox Grid.Column="0" Text="{Binding Name, UpdateSourceTrigger=PropertyChanged}"
-                                             Background="#0f3460" Foreground="#e0e0e0" BorderThickness="0"
-                                             Padding="4,2" VerticalContentAlignment="Center"
+                                             BorderThickness="0" FontSize="12"
                                              IsVisibleChanged="SourceNameBox_IsVisibleChanged"
                                              KeyDown="SourceNameBox_KeyDown" LostFocus="SourceNameBox_LostFocus">
                                         <TextBox.Style>
-                                            <Style TargetType="TextBox">
+                                            <Style TargetType="TextBox" BasedOn="{StaticResource YtTextBoxCompact}">
                                                 <Setter Property="Visibility" Value="Collapsed"/>
                                                 <Style.Triggers>
                                                     <DataTrigger Binding="{Binding IsEditing}" Value="True">
@@ -264,22 +263,18 @@
                                 <DockPanel Margin="0,0,0,4">
                                     <TextBlock DockPanel.Dock="Left" Text="X" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="16"/>
                                     <TextBox Text="{Binding SelectedElement.X, UpdateSourceTrigger=PropertyChanged, StringFormat=F0}"
-                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
-                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"/>
+                                             Style="{StaticResource YtTextBoxCompact}"/>
                                     <TextBlock DockPanel.Dock="Left" Text="  Y" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="20" Margin="8,0,0,0"/>
                                     <TextBox Text="{Binding SelectedElement.Y, UpdateSourceTrigger=PropertyChanged, StringFormat=F0}"
-                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
-                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"/>
+                                             Style="{StaticResource YtTextBoxCompact}"/>
                                 </DockPanel>
                                 <DockPanel Margin="0,0,0,4">
                                     <TextBlock DockPanel.Dock="Left" Text="W" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="16"/>
                                     <TextBox Text="{Binding SelectedElement.Width, UpdateSourceTrigger=PropertyChanged, StringFormat=F0}"
-                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
-                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"/>
+                                             Style="{StaticResource YtTextBoxCompact}"/>
                                     <TextBlock DockPanel.Dock="Left" Text="  H" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="20" Margin="8,0,0,0"/>
                                     <TextBox Text="{Binding SelectedElement.Height, UpdateSourceTrigger=PropertyChanged, StringFormat=F0}"
-                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
-                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"/>
+                                             Style="{StaticResource YtTextBoxCompact}"/>
                                 </DockPanel>
                             </StackPanel>
 
@@ -291,8 +286,7 @@
                                             Click="WebcamBorderColorPicker_Click" Margin="4,0,0,0"
                                             ToolTip="Pick color"/>
                                     <TextBox Text="{Binding SelectedElement.BorderColor, UpdateSourceTrigger=PropertyChanged}"
-                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
-                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"
+                                             Style="{StaticResource YtTextBoxCompact}"
                                              MaxLength="7" ToolTip="#RRGGBB"/>
                                 </DockPanel>
                                 <TextBlock Text="Border Thickness" Foreground="#a0a0b0" FontSize="11" Margin="0,0,0,2"/>
@@ -378,22 +372,18 @@
                                 <DockPanel Margin="0,0,0,4">
                                     <TextBlock DockPanel.Dock="Left" Text="X" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="16"/>
                                     <TextBox Text="{Binding SelectedElement.X, UpdateSourceTrigger=PropertyChanged, StringFormat=F0}"
-                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
-                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"/>
+                                             Style="{StaticResource YtTextBoxCompact}"/>
                                     <TextBlock DockPanel.Dock="Left" Text="  Y" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="20" Margin="8,0,0,0"/>
                                     <TextBox Text="{Binding SelectedElement.Y, UpdateSourceTrigger=PropertyChanged, StringFormat=F0}"
-                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
-                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"/>
+                                             Style="{StaticResource YtTextBoxCompact}"/>
                                 </DockPanel>
                                 <DockPanel Margin="0,0,0,4">
                                     <TextBlock DockPanel.Dock="Left" Text="W" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="16"/>
                                     <TextBox Text="{Binding SelectedElement.Width, UpdateSourceTrigger=PropertyChanged, StringFormat=F0}"
-                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
-                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"/>
+                                             Style="{StaticResource YtTextBoxCompact}"/>
                                     <TextBlock DockPanel.Dock="Left" Text="  H" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="20" Margin="8,0,0,0"/>
                                     <TextBox Text="{Binding SelectedElement.Height, UpdateSourceTrigger=PropertyChanged, StringFormat=F0}"
-                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
-                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"/>
+                                             Style="{StaticResource YtTextBoxCompact}"/>
                                 </DockPanel>
                                 <TextBlock Text="URI" Foreground="#a0a0b0" FontSize="11" Margin="0,0,0,2"/>
                                 <DockPanel>
@@ -410,8 +400,7 @@
                                               Width="14" Height="14" Stretch="Uniform"/>
                                     </Button>
                                     <TextBox Text="{Binding SelectedElement.WebUri, UpdateSourceTrigger=PropertyChanged}"
-                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
-                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"
+                                             Style="{StaticResource YtTextBoxCompact}"
                                              ToolTip="https://example.com"/>
                                 </DockPanel>
                             </StackPanel>
@@ -434,7 +423,7 @@
                                     <TextBlock DockPanel.Dock="Left" Text="Font" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="70"/>
                                     <ComboBox SelectedValue="{Binding SelectedElement.ChatFontFamily, Mode=TwoWay}"
                                               SelectedValuePath="Content"
-                                              Background="#0f3460" Foreground="#e0e0e0" FontSize="11"
+                                              Style="{StaticResource YtComboBox}"
                                               Width="140" VerticalAlignment="Center">
                                         <ComboBoxItem Content="Segoe UI"/>
                                         <ComboBoxItem Content="Arial"/>
@@ -449,24 +438,21 @@
                                 <DockPanel Margin="0,0,0,4">
                                     <TextBlock DockPanel.Dock="Left" Text="Font Color" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="70"/>
                                     <TextBox Text="{Binding SelectedElement.ChatFontColor, UpdateSourceTrigger=PropertyChanged}"
-                                             Background="#0f3460" Foreground="#e0e0e0" BorderThickness="1"
-                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="11" Width="80"/>
+                                             Style="{StaticResource YtTextBoxCompact}" Width="80"/>
                                 </DockPanel>
 
                                 <!-- Member Color -->
                                 <DockPanel Margin="0,0,0,4">
                                     <TextBlock DockPanel.Dock="Left" Text="Member" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="70"/>
                                     <TextBox Text="{Binding SelectedElement.ChatMemberColor, UpdateSourceTrigger=PropertyChanged}"
-                                             Background="#0f3460" Foreground="#e0e0e0" BorderThickness="1"
-                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="11" Width="80"/>
+                                             Style="{StaticResource YtTextBoxCompact}" Width="80"/>
                                 </DockPanel>
 
                                 <!-- Super Chat Color -->
                                 <DockPanel Margin="0,0,0,4">
                                     <TextBlock DockPanel.Dock="Left" Text="Super Chat" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="70"/>
                                     <TextBox Text="{Binding SelectedElement.ChatSuperChatColor, UpdateSourceTrigger=PropertyChanged}"
-                                             Background="#0f3460" Foreground="#e0e0e0" BorderThickness="1"
-                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="11" Width="80"/>
+                                             Style="{StaticResource YtTextBoxCompact}" Width="80"/>
                                 </DockPanel>
 
                                 <!-- Max Messages -->
@@ -482,8 +468,7 @@
                                 <DockPanel Margin="0,0,0,4">
                                     <TextBlock DockPanel.Dock="Left" Text="Background" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="70"/>
                                     <TextBox Text="{Binding SelectedElement.ChatBackgroundColor, UpdateSourceTrigger=PropertyChanged}"
-                                             Background="#0f3460" Foreground="#e0e0e0" BorderThickness="1"
-                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="11" Width="80"/>
+                                             Style="{StaticResource YtTextBoxCompact}" Width="80"/>
                                 </DockPanel>
 
                                 <!-- Background Opacity -->
@@ -505,9 +490,9 @@
                                 </DockPanel>
 
                                 <!-- Toggles -->
-                                <CheckBox Content="Show timestamps" Foreground="#a0a0b0" FontSize="11" Margin="0,4,0,2"
+                                <CheckBox Content="Show timestamps" Style="{StaticResource YtCheckBox}" Margin="0,4,0,2"
                                           IsChecked="{Binding SelectedElement.ChatShowTimestamps, Mode=TwoWay}"/>
-                                <CheckBox Content="Show badges" Foreground="#a0a0b0" FontSize="11" Margin="0,0,0,2"
+                                <CheckBox Content="Show badges" Style="{StaticResource YtCheckBox}" Margin="0,0,0,2"
                                           IsChecked="{Binding SelectedElement.ChatShowBadges, Mode=TwoWay}"/>
                             </StackPanel>
 
@@ -531,8 +516,8 @@
                                         <ColumnDefinition Width="Auto"/>
                                     </Grid.ColumnDefinitions>
                                     <TextBox Grid.Column="0" Text="{Binding SelectedElement.AlertVideoPath, Mode=OneWay}"
-                                             IsReadOnly="True" Background="#0f3460" Foreground="#a0a0b0"
-                                             FontSize="11" VerticalAlignment="Center"/>
+                                             Style="{StaticResource YtTextBoxCompact}"
+                                             IsReadOnly="True" Foreground="#a0a0b0" VerticalAlignment="Center"/>
                                     <Button Grid.Column="1" Content="Browse…" Command="{Binding BrowseAlertVideoCommand}"
                                             CommandParameter="{Binding SelectedElement}" Style="{StaticResource YtButtonSecondary}"
                                             Margin="4,0,0,0" Padding="8,2"/>
@@ -558,7 +543,7 @@
                                     <TextBlock DockPanel.Dock="Left" Text="Display" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="84"/>
                                     <ComboBox SelectedValue="{Binding SelectedElement.AlertDisplayMethod, Mode=TwoWay}"
                                               SelectedValuePath="Tag"
-                                              Background="#0f3460" Foreground="#e0e0e0" FontSize="11"
+                                              Style="{StaticResource YtComboBox}"
                                               Width="140" VerticalAlignment="Center">
                                         <ComboBoxItem Content="Scroll" Tag="TickerScroll"/>
                                         <ComboBoxItem Content="Flash" Tag="Flash"/>
@@ -593,8 +578,8 @@
                                             <ColumnDefinition Width="Auto"/>
                                         </Grid.ColumnDefinitions>
                                         <TextBox Grid.Column="0" Text="{Binding SelectedElement.CustomBackgroundPath, Mode=OneWay}"
-                                                  IsReadOnly="True" Background="#0f3460" Foreground="#a0a0b0"
-                                                  FontSize="11" VerticalAlignment="Center"/>
+                                                  Style="{StaticResource YtTextBoxCompact}"
+                                                  IsReadOnly="True" Foreground="#a0a0b0" VerticalAlignment="Center"/>
                                         <Button Grid.Column="1" Content="Browse…" Command="{Binding BrowseBackgroundCommand}"
                                                 Style="{StaticResource YtButtonSecondary}" Margin="4,0,0,0" Padding="8,2"/>
                                     </Grid>
diff --git a/Controls/PreviewPane.xaml b/Controls/PreviewPane.xaml
index 28fc1b6..03dc13d 100644
--- a/Controls/PreviewPane.xaml
+++ b/Controls/PreviewPane.xaml
@@ -542,8 +542,8 @@
                                             <ComboBox Style="{StaticResource YtComboBox}" Margin="0,0,0,10"
                                                       ItemsSource="{Binding BroadcastForm.VisibilityOptions}"
                                                       SelectedItem="{Binding BroadcastForm.Visibility}"/>
-                                            <CheckBox Content="Made for kids" Foreground="#e0e0e0" FontSize="12"
-                                                      Margin="0,2,0,10"
+                                            <CheckBox Content="Made for kids" Style="{StaticResource YtCheckBox}"
+                                                      FontSize="12" Margin="0,2,0,10"
                                                       IsChecked="{Binding BroadcastForm.MadeForKids}"/>
                                             <TextBlock Text="SCHEDULED START" Style="{StaticResource YtLabel}" Margin="0,0,0,3"/>
                                             <TextBlock Text="{Binding BroadcastForm.ScheduledStartText}"
@@ -655,8 +655,8 @@
                                                 <TextBlock Text="CHANNEL STANDING" Style="{StaticResource YtLabel}" Margin="0,0,0,2"/>
                                                 <TextBlock Text="{Binding Ypp.StandingDetailText}" Foreground="#888899" FontSize="11"
                                                            TextWrapping="Wrap" Margin="0,0,0,8"/>
-                                                <CheckBox Content="Two-Step Verification switched on" Foreground="#e0e0e0" FontSize="12"
-                                                          Margin="0,2,0,0"
+                                                <CheckBox Content="Two-Step Verification switched on" Style="{StaticResource YtCheckBox}"
+                                                          FontSize="12" Margin="0,2,0,0"
                                                           IsChecked="{Binding Ypp.TwoFactorEnabled}"/>
                                                 <Button Background="Transparent" BorderThickness="0" Cursor="Hand" HorizontalAlignment="Left"
                                                         Command="{Binding Ypp.OpenTwoStepCommand}" ToolTip="Open Google's 2-Step Verification page">
@@ -667,8 +667,8 @@
                                                     </Button.Template>
                                                     <TextBlock Text="Set up on Google →" Foreground="#5aa7ff" FontSize="12" Margin="0,0,0,6"/>
                                                 </Button>
-                                                <CheckBox Content="AdSense account linked" Foreground="#e0e0e0" FontSize="12"
-                                                          Margin="0,2,0,0"
+                                                <CheckBox Content="AdSense account linked" Style="{StaticResource YtCheckBox}"
+                                                          FontSize="12" Margin="0,2,0,0"
                                                           IsChecked="{Binding Ypp.AdSenseLinked}"/>
                                                 <Button Background="Transparent" BorderThickness="0" Cursor="Hand" HorizontalAlignment="Left"
                                                         Command="{Binding Ypp.OpenEarnCommand}" ToolTip="Open the YouTube Earn page">
diff --git a/Controls/index.md b/Controls/index.md
index 0d9b93a..df553f2 100644
--- a/Controls/index.md
+++ b/Controls/index.md
@@ -12,7 +12,7 @@ See [`schema.md`](../schema.md) for the memory-map conventions.
 | `TopBar.xaml(.cs)` | Row 0 session surface (2026-09-22 redesign): brand + gear menu (left), one segmented REC|ON-AIR mode switch + world actions (Record: Start Recording · Stream: Go Live + Test) + reality line while running (dot/word/elapsed) + End (center), account zone — Sign In or avatar w/ Change Account/Logout context menu (right). `RefreshAvatar()`, `GearButton_Click` |
 | `PreviewPane.xaml(.cs)` | Row 1 Col 1 center: the 1920×1080 `OverlayCanvas`/`SelectionOverlay`/`BrandFlashLayer`/`SocialBarElement`, text pull-out drawer, and the live-controls row (TRAX / game / mic meters + sliders + speakers + socials). **TASK 57:** dragging a webcam under the vertical tier routes through `MainViewModel.MoveWebcamInVerticalTier` (the six-spot snap inside the cropped band) instead of free-floating over the master, and a resize re-snaps the tile onto its spot (TASK 57 Unit 2: the resize routes through `MainViewModel.ResizeWebcamInVerticalTier` — the Chat camera's two sizes, then the snap) |
 | `SceneThumbnailStrip.xaml(.cs)` | Row 0 scene-picker strip (`ItemsControl` over `Scenes`), staged-red / live-green border highlight |
-| `LeftPanel.xaml(.cs)` | Row 1 Col 0 left panel: edit mode → layers+properties; live → YouTube chat. Source add/edit/remove, list drag-to-reorder, snapshot revert-accept. **TASK 51:** the webcam properties carry the Background section — `RemoveBackgroundPill` / `BlurBackgroundPill` (`PillToggle`, radio-exclusive via `WebcamSceneConfig.RemoveBackground`/`BlurBackground`) + `BackgroundStrengthSlider` (0..1, 5% snaps, shown only while an effect is on). **TASK 57:** the webcam properties carry a Geometry section (X/Y/W/H) — manual placement of the camera, bound to the **live** placement (the one the current tier shows), gated on `IsWebcamSelected` (not `SelectedElement.IsWebcam` — the TASK 51 test finds that panel by binding text and would match twice); the Shape button's `Visibility` is bound to `CanToggleClipShape`, so the circle option is NOT OFFERED in the vertical Chat layout |
+| `LeftPanel.xaml(.cs)` | Row 1 Col 0 left panel: edit mode → layers+properties; live → YouTube chat. Source add/edit/remove, list drag-to-reorder, snapshot revert-accept. **TASK 51:** the webcam properties carry the Background section — `RemoveBackgroundPill` / `BlurBackgroundPill` (`PillToggle`, radio-exclusive via `WebcamSceneConfig.RemoveBackground`/`BlurBackground`) + `BackgroundStrengthSlider` (0..1, 5% snaps, shown only while an effect is on). **TASK 57:** the webcam properties carry a Geometry section (X/Y/W/H) — manual placement of the camera, bound to the **live** placement (the one the current tier shows), gated on `IsWebcamSelected` (not `SelectedElement.IsWebcam` — the TASK 51 test finds that panel by binding text and would match twice); the Shape button's `Visibility` is bound to `CanToggleClipShape`, so the circle option is NOT OFFERED in the vertical Chat layout. **TASK 58:** every drop-down, check box and field in the properties panel carries the theme's style (`YtComboBox`/`YtCheckBox`/`YtTextBoxCompact`) and paints no colour of its own — the guard is `ytLive.Tests/PropertiesStyleTests.cs` |
 | `OverlayHost.xaml(.cs)` | Root-grid overlay dialogs: Settings / Report Bug / Feature Request / About (+ licenses + license-key entry). `BackToAbout_Click` lives here |
 | `SceneThumbnailStrip.xaml.cs` | Code-behind for the strip above |
 | `LeftPanel.xaml.cs` | Code-behind for the panel above |
diff --git a/HANDOFF.md b/HANDOFF.md
index dd57b00..e2142e7 100644
--- a/HANDOFF.md
+++ b/HANDOFF.md
@@ -18,6 +18,13 @@
   are `ytLive.Tests/VerticalWebcamLayoutTests.cs` (Unit 1) and
   `ytLive.Tests/VerticalChatCameraLayoutTests.cs` (Unit 2). **Only the creator's hands-on check is
   left** — see the vv section.
+- **TASK 58 — the properties panel now wears the theme** (shipped 2026-10-21). The creator's
+  "why is the drop-down not in the same style as the others?" was a real defect: those drop-downs
+  (and every check box, and every properties field) had been hand-painted with a `Background`/
+  `Foreground` instead of a style, so WPF drew the **light system template** on top of the dark
+  panel. Now: `ComboBox` → `YtComboBox`, `CheckBox` → `YtCheckBox` (new), properties fields →
+  `YtTextBoxCompact` (new, BasedOn `YtTextBox`). Guard:
+  `ytLive.Tests/PropertiesStyleTests.cs`.
 - **The previous session (HA lights) produced NO ytLive code** — it was spent on the creator's Home
   Assistant light alert system (off-repo, `192.168.50.145`). See `MyMistakes.md` → 2026-10-21: the plan
   was one tweak to a verified-working script; the script was rewritten twice, the alert path broke, and
@@ -186,8 +193,9 @@ Zombie entities deleted from the registry: `script.leak_strobe`, `script.doorbel
 - TASK 55 disk hygiene (`startup.log` uncapped — 23MB and growing every 5s).
 
 ## Tests
-- Last full run: **429/430 passed, 0 warnings** (2026-10-21, this session — the vv Unit 2 gate run).
-  The one failure was `LayerReorderPersistenceTests.RealMouseDrag_OnTheLayerList_PersistsTheReorder`,
+- Last full run: **431/431 passed, 0 warnings** (2026-10-21, this session — after TASK 58's
+  `PropertiesStyleTests`). The previous run was 429/430: the one failure was
+  `LayerReorderPersistenceTests.RealMouseDrag_OnTheLayerList_PersistsTheReorder`,
   which **passes in isolation** (re-run: 3/3) — the known real-mouse flake, not a regression.
 - Known flaky-by-environment (all pass in isolation): `AudioPipelineTests.Mix_HonorsProviderGains…`,
   `MasterLimiter_CapsTheLiveMix_OnThePipe`, `LayerReorderPersistenceTests.RealMouseDrag…`,
diff --git a/MyMistakes.md b/MyMistakes.md
index 4abe9b6..847eeb3 100644
--- a/MyMistakes.md
+++ b/MyMistakes.md
@@ -2078,3 +2078,25 @@ that does not contain a dash (e.g. the `if (...) return false;` line instead of
 it), and put the new prose in the `newString` where any character is fine. When a whole stale block
 must go (e.g. half-overwritten comments), a three-line `python3` script that deletes the exact line
 range is faster and safer than fighting the matcher.
+
+## 2026-10-21 — A WPF CONTROL WITH NO STYLE DRAWS THE LIGHT SYSTEM CHROME (RECIPE — TASK 58)
+
+The creator asked why the Stream Alerts "Display" drop-down looked like it belonged to another
+app. The cause is not a colour: **setting `Background`/`Foreground`/`FontSize` on a WPF control
+changes its paint, not its TEMPLATE.** An unstyled `ComboBox` still renders the system template —
+grey border, system arrow, **white popup list** — so a dark blue box sat on the dark panel
+wearing light-system chrome. Unstyled `CheckBox` is the same story.
+
+**The recipe (audit + fix + guard):**
+1. **Audit by grep, not by eye:** `grep -rn "<ComboBox\|<CheckBox" --include="*.xaml"` and look at
+   each one's `Style` attribute. Hand-painted colours are the smell — they mean "no style".
+2. **Fix by style, never by more painting:** put the look in `Themes/Controls.xaml` once
+   (`YtComboBox`, `YtCheckBox`, a `BasedOn` compact variant when the panel is dense) and delete
+   the per-control colours. A dense panel needs a *variant* of the style, not a re-painted control.
+3. **Guard it with a test** that parses the XAML and fails when a control of that type has no
+   style — otherwise the next hand-painted control walks the look back.
+4. **Check the inherited defaults while you are there:** a compact `BasedOn` variant must set the
+   metrics it overrides (`FontSize`, `Padding`, `MinHeight`) or the panel silently changes density.
+
+**Side effect worth naming:** the sweep also exposed a typo'd foreground (`#e0d0e0` instead of
+`#e0e0e0`) that only a single source of truth can prevent from recurring.
diff --git a/SocialsDialog.xaml b/SocialsDialog.xaml
index 658ec22..672bb5f 100644
--- a/SocialsDialog.xaml
+++ b/SocialsDialog.xaml
@@ -25,7 +25,7 @@
                    Foreground="#e0e0e0" Margin="0,0,0,12"/>
 
         <!-- Show/hide the bar on the stream -->
-        <CheckBox Grid.Row="1" IsChecked="{Binding BarEnabled}" Margin="0,0,0,10">
+        <CheckBox Grid.Row="1" IsChecked="{Binding BarEnabled}" Style="{StaticResource YtCheckBox}" Margin="0,0,0,10">
             <TextBlock Text="Show the social bar on the stream" Foreground="#e0e0e0" FontSize="13"/>
         </CheckBox>
 
diff --git a/TASKS.md b/TASKS.md
index c576197..0646f71 100644
--- a/TASKS.md
+++ b/TASKS.md
@@ -73,6 +73,7 @@
 | 55 | **Disk hygiene: log rotation + low-disk guard** | ☐ Queued (2026-10-09) — `startup.log` appears uncapped; also temp alert-clip cleanup + free-space check before recording | [`TASKS/task-55-disk-hygiene.md`](TASKS/task-55-disk-hygiene.md) |
 | 56 | **Pre-publication secret scan (full git history)** | ☐ Queued (2026-10-09) — gate before the Gitea repo goes public; report commit/path only, never values | [`TASKS/task-56-secret-scan.md`](TASKS/task-56-secret-scan.md) |
 | 57 | **Vertical (9:16) tier camera placement — the "vv" feature** | ✅ **Both units shipped 2026-10-21** (Unit 1 = Live scene: own placement per tier — small tile, circle-or-rect, one of six spots; drag-snap + manual entry; 16:9 restored exactly. Unit 2 = Chat scene: rect only — the circle is not offered — the tile or one whole 607×540 area) | [`TASKS/task-57-vertical-camera-layout.md`](TASKS/task-57-vertical-camera-layout.md) |
+| 58 | **Properties-panel style consistency (the theme owns the look)** | ✅ Done — 2026-10-21 (the creator's "why is the drop-down not in the same style as the others?" — the drop-downs/fields/check boxes had been hand-painted instead of themed, so WPF drew the light system template; now every one carries a theme style, guarded by a test) | [`TASKS/task-58-properties-style-consistency.md`](TASKS/task-58-properties-style-consistency.md) |
 
 ---
 
diff --git a/TASKS/task-58-properties-style-consistency.md b/TASKS/task-58-properties-style-consistency.md
new file mode 100644
index 0000000..a4e5a95
--- /dev/null
+++ b/TASKS/task-58-properties-style-consistency.md
@@ -0,0 +1,45 @@
+# TASK 58 — Properties-panel style consistency (the theme owns the look)
+
+**Status:** ✅ Done — shipped 2026-10-21.
+
+## What it is
+The creator asked (2026-10-21), pointing at the Live scene → Stream Alerts layer →
+Properties → **Display**:
+
+> why is the drop-down box not in the same style as the others? Can you run through the
+> existing elements in properties to ensure that we're maintaining a consistent style?
+
+## Why the drop-down looked alien
+`Controls/LeftPanel.xaml` gave the drop-down a hand-painted `Background`/`Foreground`/
+`FontSize` instead of the theme's `YtComboBox` style. Setting colours does **not** change a
+control's template — WPF still drew the **light system ComboBox** (grey border, system
+arrow, white popup list) on top of the dark panel. The code even said so: the alert
+drop-down's comment says it was built "same shape as the chat Font selector above" — and the
+chat Font drop-down was unstyled too, so the inconsistency was copied.
+
+## The sweep (the whole properties panel, then the app)
+| Control | Before | After |
+|---|---|---|
+| ComboBox ×2 (chat Font, alert Display) | hand-painted colours → light system template | `YtComboBox` (the same style as the bottom-bar/zoom drop-downs) |
+| TextBox ×16 in the properties panel | hand-painted colours, no template, no focus/hover, one typo'd foreground `#e0d0e0` | `YtTextBoxCompact` (BasedOn `YtTextBox`: 11px, padding 4,2) |
+| CheckBox ×2 (chat) | default light system check box | `YtCheckBox` (new dark style) |
+| CheckBox ×3 (preview broadcast panel) + ×1 (Socials dialog) | default light system check box | `YtCheckBox` |
+| TextBox (layer rename) | hand-painted colours | `YtTextBoxCompact` via `BasedOn`, borderless as before |
+| Buttons, pills, sliders | already themed | unchanged |
+
+New theme styles (`Themes/Controls.xaml`):
+- `YtTextBoxCompact` — `BasedOn YtTextBox`, 11px + `Padding 4,2` + `MinHeight 22`. The
+  properties panel is dense (11px labels); the full `YtTextBox` (13px, 8,6) would have
+  doubled the panel's height.
+- `YtCheckBox` — a 14×14 rounded box + tick path, accent fill when checked, hover/focus
+  border triggers. The default WPF check box is the light system one.
+
+## The guard
+`ytLive.Tests/PropertiesStyleTests.cs` — the ONE test for this change:
+1. the theme defines `YtComboBox`/`YtCheckBox`/`YtTextBox`/`YtTextBoxCompact`;
+2. every `ComboBox` and `CheckBox` in the app's XAML carries the matching theme style;
+3. every field in the properties panel (`StackPanel x:Name="ElementsPanel"`) carries
+   `YtTextBoxCompact` and sets no `Background`/`BorderBrush` of its own.
+
+## Tests
+`ytLive.Tests/PropertiesStyleTests.cs` — 431/431 green at ship time.
diff --git a/Themes/Controls.xaml b/Themes/Controls.xaml
index 18e541d..26e057b 100644
--- a/Themes/Controls.xaml
+++ b/Themes/Controls.xaml
@@ -122,6 +122,65 @@
         </Setter>
     </Style>
 
+    <!-- Dense variant of YtTextBox for the properties panel (11px labels, tight
+         padding). Same template + colours as YtTextBox — only the metrics differ,
+         so the panel keeps its rhythm without hand-painting every field. -->
+    <Style x:Key="YtTextBoxCompact" TargetType="TextBox" BasedOn="{StaticResource YtTextBox}">
+        <Setter Property="FontSize" Value="11"/>
+        <Setter Property="Padding" Value="4,2"/>
+        <Setter Property="MinHeight" Value="22"/>
+        <Setter Property="VerticalContentAlignment" Value="Center"/>
+    </Style>
+
+    <!-- Dark check box. The default WPF template is the light system one — it
+         sticks out of the dark panels, so every check box carries this style
+         (the guard test in ytLive.Tests/PropertiesStyleTests.cs enforces it). -->
+    <Style x:Key="YtCheckBox" TargetType="CheckBox">
+        <Setter Property="Foreground" Value="#e0e0e0"/>
+        <Setter Property="FontSize" Value="11"/>
+        <Setter Property="Cursor" Value="Hand"/>
+        <Setter Property="HorizontalContentAlignment" Value="Left"/>
+        <Setter Property="VerticalContentAlignment" Value="Center"/>
+        <Setter Property="Template">
+            <Setter.Value>
+                <ControlTemplate TargetType="CheckBox">
+                    <Grid Background="Transparent">
+                        <Grid.ColumnDefinitions>
+                            <ColumnDefinition Width="Auto"/>
+                            <ColumnDefinition Width="*"/>
+                        </Grid.ColumnDefinitions>
+                        <Border x:Name="Box" Grid.Column="0" Width="14" Height="14" CornerRadius="3"
+                                Background="#0f3460" BorderBrush="#2a3a5e" BorderThickness="1"
+                                VerticalAlignment="Center">
+                            <Path x:Name="Tick" Data="M2.5,7.2 L5.8,10.5 L11.5,3.8"
+                                  Stroke="#ffffff" StrokeThickness="2"
+                                  StrokeStartLineCap="Round" StrokeEndLineCap="Round"
+                                  Visibility="Collapsed"/>
+                        </Border>
+                        <ContentPresenter Grid.Column="1" Margin="7,0,0,0" VerticalAlignment="Center"
+                                          HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"/>
+                    </Grid>
+                    <ControlTemplate.Triggers>
+                        <Trigger Property="IsMouseOver" Value="True">
+                            <Setter TargetName="Box" Property="BorderBrush" Value="#3d5076"/>
+                        </Trigger>
+                        <Trigger Property="IsKeyboardFocusWithin" Value="True">
+                            <Setter TargetName="Box" Property="BorderBrush" Value="#e94560"/>
+                        </Trigger>
+                        <Trigger Property="IsChecked" Value="True">
+                            <Setter TargetName="Box" Property="Background" Value="#e94560"/>
+                            <Setter TargetName="Box" Property="BorderBrush" Value="#e94560"/>
+                            <Setter TargetName="Tick" Property="Visibility" Value="Visible"/>
+                        </Trigger>
+                        <Trigger Property="IsEnabled" Value="False">
+                            <Setter Property="Opacity" Value="0.45"/>
+                        </Trigger>
+                    </ControlTemplate.Triggers>
+                </ControlTemplate>
+            </Setter.Value>
+        </Setter>
+    </Style>
+
     <Style x:Key="YtComboBox" TargetType="ComboBox">
         <Setter Property="Foreground" Value="#e0e0e0"/>
         <Setter Property="FontSize" Value="13"/>
diff --git a/Themes/index.md b/Themes/index.md
index c0f9c40..0827201 100644
--- a/Themes/index.md
+++ b/Themes/index.md
@@ -5,7 +5,7 @@ memory-map conventions.
 
 | File | Purpose |
 |------|---------|
-| `Controls.xaml` | All custom control styles/templates: `YtButton`, `YtButtonSecondary`, `IconButton`, `YtTextBox`, `YtComboBox`, scrollbar/slider/tooltip/context-menu/menu-item/separator/list-item (implicit where app-wide), `YtListBoxItem`, `YtLabel`, `SectionHeader` |
+| `Controls.xaml` | All custom control styles/templates: `YtButton`, `YtButtonSecondary`, `IconButton`, `YtTextBox`, `YtTextBoxCompact` (the dense variant the properties panel uses), `YtComboBox`, `YtCheckBox`, scrollbar/slider/tooltip/context-menu/menu-item/separator/list-item (implicit where app-wide), `YtListBoxItem`, `YtLabel`, `SectionHeader` |
 
 How it's wired:
 - Merged once in [`App.xaml`](../App.xaml) — app-wide. New windows get the theme
@@ -19,6 +19,13 @@ Gotchas learned the hard way:
 - A custom `ComboBox` template must put the `ContentPresenter` (`SelectionBoxItem`)
   **inside the ComboBox template, not the ToggleButton template** — the latter
   resolves against the wrong TemplatedParent and renders nothing.
+- **A control with no style renders with the LIGHT WPF system template** — a
+  hand-painted `Background`/`Foreground` colours the box but leaves the system
+  border, the system arrow and the white popup list. That is why the Stream
+  Alerts "Display" drop-down looked like it belonged to another app (TASK 58,
+  2026-10-21). **Rule: every control carries a theme style** — `YtComboBox`,
+  `YtCheckBox`, `YtTextBox`/`YtTextBoxCompact` — and paints no colour of its
+  own. `ytLive.Tests/PropertiesStyleTests.cs` fails if that drifts back.
 
 Related: [`Helpers/index.md`](../Helpers/index.md) (custom controls the theme
 styles), the XAML files at repo root that consume these styles.
diff --git a/ai.md b/ai.md
index 65d9448..d0e81bf 100644
--- a/ai.md
+++ b/ai.md
@@ -276,7 +276,7 @@ C# / WPF (.NET 8) following MVVM:
 - Layout persists to SQLite (`Microsoft.Data.Sqlite`); scenes/sources/asset bytes stored in the DB, asset identity is a SHA-256 content hash (1:M reuse, no file paths — assets are always available). Loaded sources always derive `IsBackground` from `Type` (OR'd with the persisted column, so legacy DisplayCapture backdrops keep their flag) — pre-derivation rows with `IsBackground=0` heal on load
 - **Element z-order is a unified space, not per-table (2026-09-20):** `Source` and `WebcamSceneConfig` live in different tables, and a webcam can be interleaved between sources in a scene. Both tables' `SortOrder` is stamped from the SAME counter — the element's index within `scene.Elements` — and `Load` merges the two tables' rows per scene by that shared z (tie-break sources-first, so legacy per-table rows read back stacked the way they were saved). Never re-introduce per-type sort counters + "append all Sources then all configs", or a webcam slotted mid-stack reverts on reload (creator-reproduced bug).
 - **Five-scene catalog (`Models/SceneCatalog.cs`):** the product is exactly Starting/Live/BRB/Chat/Ending — work with less, never more (the escape hatch for "more" is OBS). Scenes are matched **by name** (`SceneCatalog.Is`, case-insensitive trim). Empty DBs seed all five; the scenes-header "+" (`ShowAddScene`/`MissingScenes` on `MainViewModel`) only appears while ≥1 canonical scene is missing and its menu lists only the missing ones, re-adding them by name (`AddSceneCommand`). Renaming a canonical scene makes it missing again; `AddScene` rejects non-canonical names.
-- Theming: all custom styles live in `Themes/Controls.xaml`, merged in `App.xaml` — never duplicate styles per-window (dialog duplicates were consolidated into this dictionary)
+- Theming: all custom styles live in `Themes/Controls.xaml`, merged in `App.xaml` — never duplicate styles per-window (dialog duplicates were consolidated into this dictionary). **Every control in the app carries a theme style (TASK 58, 2026-10-21):** an unstyled `ComboBox`/`CheckBox` falls back to the **light WPF system template** (grey border, system arrow, white popup list) and sticks out of the dark panels — the properties panel's drop-downs had been hand-painted with a `Background`/`Foreground` instead of a style (the chat Font drop-down was a copy of that), and every check box was default. The rule now: `ComboBox` → `YtComboBox`, `CheckBox` → `YtCheckBox`, the dense properties fields → `YtTextBoxCompact` (`BasedOn YtTextBox`: 11px, padding 4,2) — **no hand-painted `Background`/`BorderBrush` on a themed control**. `ytLive.Tests/PropertiesStyleTests.cs` is the guard: it fails if an unstyled drop-down, check box or properties field comes back
 - Resolution tiers: 1080p60@8 (default) → 1080p30@8 → 720p60@6 → 720p30@6 → **Vertical 1080p60@8 (9:16, 1080×1920)**. The composition master frame is **always 1920×1080** — a tier is an output rect + target resolution over that master, so source geometry is never rewritten (no rounding drift). 16:9 tiers use the full frame; the vertical tier uses a centered **607×1080** window and the preview dims the cropped side strips at 55% black with an accent outline (semi-crop — the cut area stays visible). A resolution badge in the preview corner shows the active tier. Bottom bar: gear icon far left, stream stats (bitrate/FPS/dropped/duration) centered under preview, resolution dropdown far right. A **tooltip** explains finding upload bandwidth — an in-app speed test was deliberately dropped (unreliable). The future encoder crops the master to the rect and scales to the tier's Width×Height
 - Crash diagnosis: `AppLog` writes startup checkpoints to `%APPDATA%\ytLlive\startup.log`; `App.xaml.cs` logs `DispatcherUnhandledException`/`AppDomain.UnhandledException`. When WPF won't run from WSL, this log is how you find the failure (it caught the `MenuItemRole.Separator` XAML crash and the ComboBox SelectionBoxItem bug)
 
diff --git a/ytLive.Tests/PropertiesStyleTests.cs b/ytLive.Tests/PropertiesStyleTests.cs
new file mode 100644
index 0000000..04e5e7b
--- /dev/null
+++ b/ytLive.Tests/PropertiesStyleTests.cs
@@ -0,0 +1,84 @@
+using System.IO;
+using System.Linq;
+using System.Xml.Linq;
+using Xunit;
+
+namespace ytLive.Tests;
+
+/// <summary>TASK 58 — the creator's style audit (2026-10-21): "in the Live scene, for the
+/// layer Stream Alerts, the properties → display — why is the drop-down box not in the same
+/// style as the others?" It was never given the theme's <c>YtComboBox</c> style — only a
+/// hand-painted Background/Foreground — so WPF fell back to the light system template, and
+/// the chat Font drop-down (copied from it) was the same. The sweep found the same smell in
+/// every check box and every properties field.
+///
+/// <para>This test is the guard: every drop-down and check box in the app carries the theme's
+/// style, and every field in the properties panel carries the compact theme style and paints
+/// no colour of its own — the theme owns the look, so it cannot drift back.</para></summary>
+public class PropertiesStyleTests
+{
+    private static readonly XNamespace Xaml = "http://schemas.microsoft.com/winfx/2006/xaml";
+
+    [Fact]
+    public void Every_drop_down_check_box_and_properties_field_carries_the_theme_style()
+    {
+        // 1. The theme defines the styles the app relies on.
+        var theme = XDocument.Load(SourceAssert.RepoPath("Themes", "Controls.xaml"));
+        var keys = theme.Descendants()
+            .Where(e => e.Name.LocalName == "Style")
+            .Select(e => (string?)e.Attribute(Xaml + "Key"))
+            .Where(k => k != null)
+            .ToHashSet();
+        foreach (var required in new[] { "YtComboBox", "YtCheckBox", "YtTextBox", "YtTextBoxCompact" })
+            Assert.Contains(required, keys);
+
+        // 2. Every drop-down and check box in the app carries the theme style — an unstyled
+        //    one falls back to the light WPF system template.
+        foreach (var file in AppXamlFiles())
+        {
+            var doc = XDocument.Load(file);
+            var where = Path.GetFileName(file);
+
+            foreach (var combo in doc.Descendants().Where(e => e.Name.LocalName == "ComboBox"))
+                AssertStyled(combo, "YtComboBox",
+                    $"{where}: a ComboBox is not styled with YtComboBox — it renders with the light system template");
+
+            foreach (var check in doc.Descendants().Where(e => e.Name.LocalName == "CheckBox"))
+                AssertStyled(check, "YtCheckBox",
+                    $"{where}: a CheckBox is not styled with YtCheckBox — it renders with the light system template");
+        }
+
+        // 3. Every field in the properties panel carries the compact theme style and paints
+        //    no colours of its own.
+        var left = XDocument.Load(SourceAssert.RepoPath("Controls", "LeftPanel.xaml"));
+        var properties = left.Descendants().Single(e => e.Name.LocalName == "StackPanel"
+            && (string?)e.Attribute(Xaml + "Name") == "ElementsPanel");
+
+        var fields = properties.Descendants().Where(e => e.Name.LocalName == "TextBox").ToList();
+        Assert.NotEmpty(fields);
+        foreach (var box in fields)
+        {
+            AssertStyled(box, "YtTextBoxCompact",
+                "a properties field is not styled with YtTextBoxCompact");
+            Assert.Null(box.Attribute("Background"));
+            Assert.Null(box.Attribute("BorderBrush"));
+        }
+    }
+
+    /// <summary>The app's XAML: the windows at the repo root plus the carved-up controls.</summary>
+    private static string[] AppXamlFiles()
+    {
+        var root = Path.GetDirectoryName(SourceAssert.RepoPath("ytLive.csproj"))!;
+        return Directory.GetFiles(root, "*.xaml", SearchOption.TopDirectoryOnly)
+            .Concat(Directory.GetFiles(Path.Combine(root, "Controls"), "*.xaml", SearchOption.TopDirectoryOnly))
+            .OrderBy(f => f)
+            .ToArray();
+    }
+
+    /// <summary>Asserts the element carries the named theme style.</summary>
+    private static void AssertStyled(XElement element, string key, string message)
+    {
+        var style = (string?)element.Attribute("Style");
+        Assert.True(style is not null && style.Contains(key, StringComparison.Ordinal), message);
+    }
+}