ABCPDF Position of image in center of page

I Use AbcPdf, when I export HTML with images to pdf I use css to positioning image into center of page

<div class="alignToCenter">
                <%foreach (var item in images)
                  {%>
                            <div style="padding-left: 5px;">
                                <div style="page-break-before:always">&nbsp;</div>
                                <img src="<%= @"data:image/gif;base64," + item.ToString() %>" />
                            </div>
                <%} %>
    </div>

here is alignToCenter css

.alignToCenter{
                            height:100px;
                           /*background-color: red;*/
                            text-align: center;
                            position: absolute;
                            top:0;
                            bottom: 0;
                            left: 0;
                            right: 0;
                            margin: auto;
                        }

Now I want to add images using XImage

foreach (var item in exportPhotos)
                {
                    theDoc.Page = theDoc.AddPage();
                    XImage image = new XImage();
                    image.SetFile("path"+ item);

                    theDoc.Rect.String = image.Selection.String;
                    theDoc.HtmlOptions.PageCacheEnabled = false;

                    int theID2 = theDoc.AddImage(image);

                    while (true)
                    {
                        theDoc.FrameRect();
                        if (!theDoc.Chainable(theID2))
                            break;
                        theDoc.Page = theDoc.AddPage();
                        theID2 = theDoc.AddImageToChain(theID2);
                    }
                }

images is added but I need to display in center of the page,.. and if the Image is very big then I need to resize image