Add the Transparency Property to a Word Macro - vba

Question

I found a GREAT Macro for Word here! :D- How to include BackgroundPatternColor or HighlightColor in a Word Style definition?
I noticed that VBA has a Transparency value - https://learn.microsoft.com/en-us/office/vba/api/word.lineformat.transparency
In the Macro below, can you see any way to add Transparency to it?
Can you see any way to get it to work in this Macro?
Sub ChangeStyleColor()
Dim styl As Word.Style
Dim stylName As String
Dim color As Word.WdColor
stylName = "Theory"
color = RGB(104, 0, 266)
' the style might not exist - if not, create it
On Error Resume Next
Set styl = ActiveDocument.Styles(stylName)
On Error GoTo 0
If styl Is Nothing Then
Set styl = ActiveDocument.Styles.Add(stylName, Word.WdStyleType.wdStyleTypeCharacter)
styl.BaseStyle = Word.WdBuiltinStyle.wdStyleDefaultParagraphFont
End If
CharStyleBackgroundColor styl, color
End Sub
Sub CharStyleBackgroundColor(styl As Word.Style, color As Word.WdColor)
styl.Font.Shading.BackgroundPatternColor = color
End Sub
Many thanks,
OT
I tried just dropping in the line
Transparency = 0.5
beneath the RGB value, but that didn't work.
Then I tried dropping in
,Transparency = 0.5
That generated an error.