Change text color of the headerTCPDF

I suppose you have to change the font in the public functions Header () and Footer () in tcpdf.php . To find the color of the text:

$this->SetTextColor(0, 0, 0); 

In the Header () and / or Footer () functions and change it to your liking.

Regarding the color of the line, find:

$this->SetLineStyle(array('width' => 0.85 / $this->k, 'cap' => 'butt', 'join' => 'miter', 'dash' => 0, 'color' => array(70, 70, 70)));

And change the set of 'colors' at the end.

Or alternatively you can do it this way too:

By extending the main class and extending only its Footer () function:

// Extienda la clase TCPDF para crear encabezado y pie de página personalizados
class MYPDF extends TCPDF 
{
   // Pie de página
   public function Footer() 
   {
      //establecer el color del texto
      $this->SetTextColor(255,0,0);
    }
}
// crear nuevo documento PDF
$pdf = new MYPDF(PDF_PAGE_ORIENTATION, PDF_UNIT, PDF_PAGE_FORMAT, true, 'UTF-8', false);

  

SO Source: Change text color in header in TCPDF