/// <summary>
        /// Gets the margins for the top form
        /// </summary>
        /// <param name="topOffset">top offset (title height when border style is none or zero when border style is provided)</param>
        /// <returns>margins</returns>
        private Margins GetMargins(out int topOffset)
        {
            FormsContainerControlCollection forms = (FormsContainerControlCollection)FormsPanel.Controls;

            Margins margins = FormWrapper.GetMargins(forms.TopControl);

            topOffset = 0;
            Form topForm = forms.TopControl as Form;

            if (topForm != null)
            {
                if (topForm.FormBorderStyle == FormBorderStyle.None)
                {
                    margins.Top    = DefaultTopMargin + DefaultTitleHeight;
                    margins.Left   = DefaultLeftMargin;
                    margins.Right  = DefaultRightMargin;
                    margins.Bottom = DefaultBottomMargin;

                    topOffset = DefaultTitleHeight;
                }
            }

            return(margins);
        }