-- archive-event.php

get_header();
custom_header_styles('...', '...', '...');


-- functions.php
function header_styles($title='', $subtitle ='', $background){
	$format = '...';
	return sprintf($format, $title, $subtitle, $background);
}

add_action('konte_after_header', 'custom_header_styles');
function custom_header_styles($title='',$subtitle='',$background=''){
	echo header_styles($title, $subtitle, $background);
}