Прозрачность в VB по определённому цвету

Option Explicit
 
Private Declare Function GetWindowLong Lib 'user32' Alias 'GetWindowLongA' (ByVal hwnd As Long, ByVal nIndex As Long) As Long
Private Declare Function SetWindowLong Lib 'user32' Alias 'SetWindowLongA' (ByVal hwnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long
Private Declare Function SetLayeredWindowAttributes Lib 'user32' (ByVal hwnd As Long, ByVal crey As Byte, ByVal bAlpha As Byte, ByVal dwFlags As Long) As Long
Private Const GWL_EXSTYLE = -20
Private Const WS_EX_LAYERED = &H80000
Private Const WS_EX_TRANSPARENT = &H20&
Private Const LWA_ALPHA = &H2&
Private NormalWindowStyle As Long
 
Private Sub Form_Load()
    Dim Trans as integer ' 
    Trans = 50 'Прозрачность окна (1 - 100)
    NormalWindowStyle = GetWindowLong(Me.hwnd, GWL_EXSTYLE)
    SetWindowLong frmMain.hwnd, GWL_EXSTYLE, NormalWindowStyle Or WS_EX_LAYERED
    SetLayeredWindowAttributes frmMain.hwnd, 0, 255, LWA_ALPHA
    SetLayeredWindowAttributes frmMain.hwnd, 0, (255 * Trans)/ 100, LWA_ALPHA
End Sub