<?

$project_ids = get_field( 'project_this' );
$offset      = get_query_var( 'paged' ) > 1 ? get_query_var( 'paged' ) * 3 - 3 : 1;

$args = [
    'post_type'      => 'portfolio',
    'orderby'        => 'id',
    'order'          => 'ASC',
    'post__in'       => wp_parse_id_list( $project_ids ),
    'posts_per_page' => 3,
    'offset'         => $offset,
];

global $wp_query;
$i        = 0;
$wp_query = new WP_Query( $args );
if ( have_posts() ) : while ( have_posts() ) : the_post();
    $i ++; ?>

    <div class="col-md-12 project-item project-item-<?= $i ?>" data-id="<?
    the_ID() ?>">
        content
    </div>
<?endwhile;
endif;

$argspagi = [];
$argspagi = [
    'prev_next' => true,
    'prev_text' => __( '<i class="fa fa-long-arrow-left"></i>' ),
    'next_text' => __( '<i class="fa fa-long-arrow-right"></i>' ),
    'type'      => 'plain',
];
the_posts_pagination( $argspagi );
wp_reset_query();