Issue when converting html to pdf

[farrelwp]

I tried to convert using DinkToPDF but the PDF result is different than my HTML when i open in my browser,

Here's my DinkToPdf Setting:

     [ var globalSettings = new GlobalSettings
        {
            ColorMode = ColorMode.Color,
            Orientation = Orientation.Portrait,
            PaperSize = PaperKind.A4,
            DocumentTitle = title,
            Out = string.Empty,
        };

        var objectSettings = new ObjectSettings
        {
            PagesCount = true,
            HtmlContent = htmlBody,
            WebSettings = { DefaultEncoding = "utf-8" }
        };]

This is my html and pdf result: Html :

PDF Result:

is it a bug?or there's something wrong with my css/html code