Why @page is not working for printing an HTML page?

Question

I used the @media print attribute to custom printing of pdf file.

Everything is going fine, but I didn't succeed to make the (page count / title) work using @page.

print.css

@media print {
   @page {
        size: A4;

        @bottom-right {
            content: counter(page) " of " counter(pages);
        }
        @bottom-center {
            content: doctitle content();;
        }
    }
}

Do I need something more like a js library to make it work ?

Thank you for your help.