设置mPDF标题的左侧宽度

I am using mPDF for exporting contents as a PDF file. For creating header, I am using $mpdf->SetHeader() function like this:

$arr = array (
    'L' => array (
        'content' => 'Bozmadan sonra ıslah yapılamaz kuralının istisnası, ...',
        'font-size' => 10,
        'font-style' => 'B',
        'font-family' => 'serif'
    ),
    'R' => array (
        'content' => '{PAGENO}',
        'font-size' => 10,
        'font-style' => 'B',
        'font-family' => 'serif',
        'color'=>'#000000'
        ),
    'line' => 1
);
$mpdf->SetHeader($arr, 'O');

This gives us like this:

You see, I don't want center area but it creates. How can I code for more wider left side, narrower right side and no center area.

If you use SetHTMLHeader() instead of SetHeader(), you can style it in HTML and have more control over the layout.

$header= '<table width="100%"><tr>  
<td width="80%">Bozmadan sonra ıslah yapılamaz kuralının istisnası, ...</td>
<td width="20%">{PAGENO}</td>
</tr></table>';
$mpdf->SetHTMLHeader($header);