[Bug] Unfocused TreeViewItem background doesn't follow set theme

[CyLuGh]

Check the following items

• I have looked up relevant Issue

Description of the issue

When window loses focus, the background of the selected item in a TreeView reverts to a dark blue, not following the theme that has been set.

Package Version

6.0.3 (also tried with the latest committed code)

Environment

Windows 11

Expected Behavior

Background color should follow the theme, or maybe have a more neutral default value? (Not that I have anything against blue but some gray might appear less conflicting when having non-blue UI theme)

Reproduction

This can be seen in the demo application, simply set any non blue theme, select an item in the treeview and click outside the window.

Additional Information

No response

[chenhanghua]

you can
`

<Style Selector="TreeViewItem:selected /template/ Border"> </Style>

`