<?php $terms = (get_the_terms( get_the_ID(), 'gallery_category' )); ?> 
<div class="col-md-3 col-sm-4 col-xs-6 stm-isotope-item teacher-col gallery-col all <?php if(!empty($terms)): foreach($terms as $term):echo($term->slug).' '; endforeach; endif; ?>">
		
	<?php if(has_post_thumbnail()): ?>
		<div class="gallery_single_view">
			<div class="gallery_img">
				<?php $url_big = wp_get_attachment_image_src( get_post_thumbnail_id(get_the_id()), 'full' ); ?>
				<a class="stm_fancybox" 
					href="<?php echo esc_url($url_big[0]); ?>" 
					title="<?php _e('Watch full image', 'masterstudy'); ?>"
					data-caption="<?php the_title(); ?>"
					rel="gallery_rel">
						<?php the_post_thumbnail('img-270-180', array('class'=>'img-responsive')); ?>
				</a>
			</div>
		</div>
	<?php endif; ?>
		
</div>