ACF Example Shortcode

portfolio.php

<?php

function style_partners_grid() {
    wp_enqueue_style( 'style_partners_grid', get_stylesheet_directory_uri() . '/css/partners.css' );
}
add_action( 'wp_enqueue_scripts', 'style_partners_grid' );

function shortcode_partners_grid($params = array()) {

    $_id = time();

    ob_start();

    //echo time();

    $styles = [];

    // ---------------------------------------------------------------------------------------------------

    echo "<div class='partners'>";

    $partners_images = get_field( 'partners', 'option' );
    if ( $partners_images ) :
        foreach ( $partners_images as $partners_image ):
            $url = $partners_image['url'];
            $alt = $partners_image['alt'];
            echo "<div class='partners-item'>";
            echo "<img src='$url' alt='$alt' />";
            echo "</div>";
        endforeach;
    endif;

    echo "</div>";

    // -----------------------------------------------------------------------------------------------

    echo "<style type='text/css'>";
    echo implode('',$styles);
    echo "</style>";

    wp_reset_query();

    return ob_get_clean();

}
add_shortcode('partners', 'shortcode_partners_grid');