QWebEnginePage print pdf in Landscape

[mmjvox]

I'm trying to save a pdf file from QWebEnginePage in Landscape ,

 QWebEnginePage *m_page;

 m_page->setHtml(m_inputPath);

m_page->printToPdf(m_outputPath, QPageLayout( QPageSize(QPageSize::A4) ,
                                                   QPageLayout::Landscape,
                                                  QMarginsF()) );

but Landscape mode not working and print always in Portrait.
What wrong?

[mmjvox]

I made a little mistake.
This CSS code in my html file caused this problem.

@page {
            size: 8.27in 11.69in;
            margin: 0.86in;
        }