post_classes()

        public function post_classes($classes){
            if ( !$this->is_admin_page() ){
                $this->timer('Nebula Post Classes', 'start', '[Nebula] Markup');

                global $post;
                global $wp_query;

                if ( $wp_query->current_post === 0 ){ //If first post in a query
                    $classes[] = 'first-post';
                }
                if ( is_sticky() ){
                    $classes[] = 'sticky';
                }
                $classes[] = 'nebula-entry';

                if ( !is_page() ){
                    $classes[] = 'date-day-' . strtolower(get_the_date('l'));
                    $classes[] = 'date-ymd-' . strtolower(get_the_date('Y-m-d'));
                    $classes[] = 'date-month-' . strtolower(get_the_date('F'));
                }

                if ( !empty($post) ){
                    foreach ( get_the_category($post->ID) as $category ){
                        $classes[] = 'cat-id-' . $category->cat_ID;
                    }
                }

                $classes[] = 'author-id-' . $post->post_author;
                if ( is_multi_author() ){
                    $classes[] = 'multi-author';
                }

                //If this post has a featured image
                if ( has_post_thumbnail() ){
                    $classes[] = 'has-featured-image';
                }

                //Remove "hentry" meta class on pages or if Author Bios are disabled
                if ( is_page() || !$this->get_option('author_bios') ){
                    $classes = array_diff($classes, array('hentry'));
                }

                $this->timer('Nebula Post Classes', 'end');
            }

            return $classes;
        }