Kids education pro

<?php
    /**
     * Template Name: Portfolio Page
     *
     * @package Theme Palace
     * @subpackage Kids Education Pro
     * @since Kids Education Pro 1.0
     */
    get_header();

    $options = kids_education_pro_get_theme_options(); // get theme options
    $portfolio_ids = !empty( $options['portfolio_category'] ) ? $options['portfolio_category'] : array();
?>
    <section id="portfolio-gallery" class="page-section os-animation" data-os-animation="fadeIn">
        <div class="container">
            <div class="entry-content">
                <?php  if( !empty(  $portfolio_ids ) ){ ?>
                <nav class="portfolio-filter">
                    <ul>
                        <li class="active"><a href="#" data-filter="*"><?php esc_html_e( 'Filter all', 'kids-education-pro' ); ?></a></li>
                        <?php foreach ($portfolio_ids as $key => $portfolio_id ) {
                                $tp_category = get_category( $portfolio_id );
                                echo '<li><a href="#" data-filter=".' . esc_attr( $tp_category->slug ) . '">' . esc_html( $tp_category->name ) . '</a></li>';
                                }
                        ?>
                    </ul>
                </nav><!-- .portfolio-filter -->
                <?php }
                if( !empty( $portfolio_ids ) ){

                    $posts_per_page = 15;//get_option( 'posts_per_page', 15 ); // get posts per page  from reading option

                    $args = array(
                        'category__in'   => $portfolio_ids,
                        'post_type'      => 'post',
                        'posts_per_page' => $posts_per_page,
                    );

                    $portfolio_posts = get_posts( $args );
                ?>
                <div id="four-col" class="portfolio-wrapper">
                    <?php
                        foreach ( $portfolio_posts as $key => $portfolio_post ) {
                           $portfolio_post_id = $portfolio_post->ID; // get post id
                           $portfolio_categories = get_the_category( $portfolio_post_id ); // get post categories

                            $term_slug = '';
                           foreach ($portfolio_categories as $key => $portfolio_category) {
                                $term_slug .= $portfolio_category->slug . ' ';
                           }
                     ?>
                        <div class="portfolio-item activities <?php echo esc_attr( $term_slug ); ?>">
                            <div class="image-wrapper">
                                <?php if( has_post_thumbnail( $portfolio_post_id ) ){
                                    $img_array  = wp_get_attachment_image_src( get_post_thumbnail_id( $portfolio_post_id ), 'kids-education-pro-gallery-section-small' );
                                    $img_array_large = wp_get_attachment_image_src( get_post_thumbnail_id( $portfolio_post_id ), 'large' );
                                } else {
                                    $img_array[0]       =  get_template_directory_uri().'/assets/uploads/no-featured-image-300x300.png';
                                    $img_array_large[0] =  get_template_directory_uri().'/assets/uploads/no-featured-image-625x400.png';
                                } ?>
                                <img src="<?php echo esc_url( $img_array[0] ); ?>" alt="<?php echo esc_html( get_the_title( $portfolio_post_id ) ); ?>">
                                <div class="blue-overlay"></div>
                            </div><!-- .image-wrapper -->
                        <div class="hovercontent">
                            <a data-title="Gallery" href="<?php echo esc_url( $img_array_large[0] ) ?>" data-lightbox="masonry"><i class="fa fa-search"></i></a>
                            <a href="<?php echo esc_url( get_permalink( $portfolio_post_id ) );?>"><i class="fa fa-link"></i></a>
                            <p><a href="<?php echo esc_url( get_permalink( $portfolio_post_id ) );?>"><?php echo esc_html( get_the_title( $portfolio_post_id ) );?></a></p>
                        </div><!-- end .hover-content -->
                    </div><!-- end .portfolio-item -->
                    <?php }?>
                </div><!-- end portfolio -->
                <?php } ?>
                <div class="text-center">
                    <a href="#" id="loadmore" class="btn btn-blue"><?php esc_html_e( 'Load more', 'kids-education-pro' ) ?></a>
                </div><!-- end .button -->
            </div><!-- end .entry-content -->

        </div><!-- end .container -->
    </section><!-- #portfolio-gallery -->

<?php
    get_footer();