# 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.