We update meta tag in header of template:
ROOT/templates/gk_photo/layouts/default.php
<?php if($this->API->get('rwd', 1)) : ?>
<meta name="viewport" content="initial-scale = 1.0">
<?php else : ?>
<meta name="viewport" content="width=<?php echo $this->API->get('template_width', 1900)+40; ?>">
<?php endif; ?>
<meta name="viewport" content="width=device-width, initial-scale=1">
<meta name="viewport" content="initial-scale=1.0, width=device-width, user-scalable=yes" />