// Filter the title with a custom function
add_filter('genesis_seo_title', 'cg_site_title' );
// Add additional custom style to site header
function cg_site_title( $title ) {
// Change $custom_title text as you wish
$custom_title = '<span class="custom-title">creative</span>Genesis';
// Don't change the rest of this on down
// If we're on the front page or home page, use `h1` heading, otherwise us a `p` tag
$tag = ( is_home() || is_front_page() ) ? 'h1' : 'p';
// Compose link with title
$inside = sprintf( '<a href="%s" title="%s">%s</a>', trailingslashit( home_url() ), esc_attr( get_bloginfo( 'name' ) ), $custom_title );
// Wrap link and title in semantic markup
$title = sprintf ( '<%s class="site-title" itemprop="headline">%s</%s>', $tag, $inside, $tag );
return $title;
}