How to seperate background between two adjacent nodes in WinForms TreeViewAdv?

treeViewAdv1.BeforeNodePaint += TreeViewAdv1_BeforeNodePaint1;
 
//Customize Background of Nodes
private void TreeViewAdv1_BeforeNodePaint1(object sender, TreeNodeAdvPaintEventArgs e)
{
  LinearGradientBrush lBrush = new LinearGradientBrush(e.Node.Bounds, Color.LightGreen, Color.LightSeaGreen, LinearGradientMode.Horizontal);
  e.Graphics.FillRectangle(lBrush, e.Node.Bounds);
  e.Graphics.DrawRectangle(new Pen(Color.Red), e.Node.Bounds);
}

AddHandler treeViewAdv1.BeforeNodePaint, AddressOf TreeViewAdv1_BeforeNodePaint1
 
'Customize Background of Nodes
Private Sub TreeViewAdv1_BeforeNodePaint1(ByVal sender As Object, ByVal e As TreeNodeAdvPaintEventArgs)
 Dim lBrush As New LinearGradientBrush(e.Node.Bounds, Color.LightGreen, Color.LightSeaGreen, LinearGradientMode.Horizontal)
 e.Graphics.FillRectangle(lBrush, e.Node.Bounds)
 e.Graphics.DrawRectangle(New Pen(Color.Red), e.Node.Bounds)
End Sub