how can I add custom styles in my table... ?

[spartnernl]

how can I add custom styles in my table... ?

[MaatwebsiteSupport]

This packages has a couple of styling wrappers (see documentation).
If you want to use the other onces (see PHPExcel documentation), you can always load the class into a $var.

This example will color the text of a range of cells red.

$obj = Excel::loadView('excel')->setTitle('test')->sheet('test');
$obj->excel->getActiveSheet()
                ->getStyle('A1:B30')
                ->getFont()
                ->applyFromArray(
                    array(
                        'name' => 'Arial',
                        'color' => array(
                            'rgb' => 'FF0000'
                        )
                    )
                );
$excel->export('xls');

[MaatwebsiteSupport]

Inside the blade view file (used by loadView()) you can now use inline css styles.(See documentation for available style tags)