Issue with make bold some row

[mrizkysaragih]

$z='';
for($c=0; $c < sizeof($dis); $c++)
{
if($c==sizeof($dis)-1)
$z.=$dis[$c]->id_surat;
else
$z.=$dis[$c]->id_surat.", ";
// var_dump($z);
// var_dump($dis[$c]->baca);

    }

$z=0;
$this->datatables->select("id, nomorsurat, tanggal , pengirim, tertuju, sifatsurat");
$this->datatables->add_column('Actions', get_buttons('$1',$this->ulvl),'id');
$this->datatables->edit_column('nomorsurat',"$1","");

     $this->datatables->from('suratmasuk');
     $this->datatables->where("id in ($z)");
     echo $siap=$this->datatables->generate();        

if value baca is 0, then the row look bold, vice versa.
any idea?