/**
 * Previous/next buttons for single portfolio
 */
function custom_portfolio_prev_next() {
	$output = '';

	ob_start();
	next_post_link( '%link', '<span>' . esc_html__( 'Previous', 'polo_extension' ) . '<i class="fa fa-chevron-right"></i></span>' );
	$next_post = ob_get_clean();

	ob_start();
	previous_post_link( '%link', '<span><i class="fa fa-chevron-left"></i>' . esc_html__( 'Next', 'polo_extension' ) . '</span>' );
	$prev_post = ob_get_clean();

	$output .= '<div class="pager pager-modern text-center">';
	if ( isset( $prev_post ) && ! empty( $prev_post ) ) {
		$output .= str_replace( '<a ', '<a class="pager-prev"', $prev_post );
	} else {
		$output .= '<a class="pager-prev disabled" href="#"><span><i class="fa fa-chevron-left"></i>' . esc_html__( 'Next', 'polo_extension' ) . '</span></a>';
	}
	$output .= '<a class="pager-all" href="' . get_home_url( '/' ) . '"><span><i class="fa fa-th"></i></span></a>';
	if ( isset( $next_post ) && ! empty( $next_post ) ) {
		$output .= str_replace( '<a ', '<a class="pager-next"', $next_post );
	} else {
		$output .= '<a class="pager-next disabled" href="#"><span>' . esc_html__( 'Previous', 'polo_extension' ) . '<i class="fa fa-chevron-right"></i></span></a>';
	}
	$output .= '</div>';

	if ( is_singular( 'portfolio' ) ) {
		echo $output;
	}

}
function crum_replace_portfolio_navigation(){
    remove_action( 'polo_content_after', 'crumina_portfolio_prev_next' );
    add_action( 'polo_content_after', 'custom_portfolio_prev_next' );
}

add_action('init', 'crum_replace_portfolio_navigation');