Add the theme for the bottom sheet UI

Bug: 318310357
Bug: 298898436
Bug: 298891941
Test: build pass
Change-Id: Ibbf41a6b698f86e8e12e8e09243ce6b84efb35c7
diff --git a/packages/SettingsLib/Spa/spa/res/values/themes.xml b/packages/SettingsLib/Spa/spa/res/values/themes.xml
index 4b5a9bc..b55dd1b 100644
--- a/packages/SettingsLib/Spa/spa/res/values/themes.xml
+++ b/packages/SettingsLib/Spa/spa/res/values/themes.xml
@@ -24,4 +24,8 @@
     </style>
 
     <style name="Theme.SpaLib.Dialog" parent="Theme.Material3.DayNight.Dialog"/>
+    <style name="Theme.SpaLib.BottomSheetDialog" parent="Theme.SpaLib">
+        <item name="android:windowBackground">@android:color/transparent</item>
+        <item name="android:windowIsTranslucent">true</item>
+    </style>
 </resources>