[C#] Picturebox 위에 Grid 격자 모눈종이 그리기

private void pbZoom_Paint(object sender, PaintEventArgs e)
{
    int Xn = pbZoom.Width;
    int Yn = pbZoom.Height;
    Pen pn = new Pen(Color.FromArgb(150, 255, 255, 255));
    
    for (int y = -3; y < Yn - 1; y+=38)
    {
        e.Graphics.DrawLine(pn, 0, y, Xn, y); 
    }
    for (int x = -3; x < Xn - 1; x+=38)
    {
        e.Graphics.DrawLine(pn, x, 0, x, Yn);
    }
}