Flexslider + vertically centralised

HTML ----
	<?php

		// slideshow
		$rows = get_field('slideshow_repeater');

		if($rows) {

			echo "<!-- slideshow -->
				<div id='slideshow' class='full-width clearfix'>

					<div class='flexslider clearfix'>";
					
						echo "<ul class='slides'>";

							foreach($rows as $row) {

								echo "<li class='slide'>";

										$image_attributes 	= wp_get_attachment_image_src( $row['slide'], 'slideshow-main' );
										$alt_text 			= get_post_meta( $row['slide'], '_wp_attachment_image_alt', true);
										echo "<img src='".$image_attributes[0]."' alt='".$alt_text."'>";

								echo "</li>";

							}

						echo "</ul>";
					
					echo "</div>

				</div>
				<!-- /slideshow -->";

		}
		// slideshow

	?>
HTML ----






JS ----
	$(window).load(function(){

		if( $('.home .flexslider').length > 0 ) {
			
			$('.flexslider').flexslider({
				animation: "fade",
				slideshowSpeed: 5000,
				controlNav: false,
				directionNav: false,
				slideshow: true,
				prevText: "",
				nextText: ""
			});

		}

		// Slideshow vertically centralises the slide in the parent li
		adjustHeight();
		$(window).resize(adjustHeight);


		function adjustHeight() {
			var $li_height 				= $('#slideshow.full-width li.flex-active-slide').innerHeight();
			var $slide_image_height 	= $('#slideshow.full-width li.flex-active-slide img').innerHeight();

			if( $slide_image_height > $li_height ) {
				$('#slideshow.full-width li.flex-active-slide img').css('margin-top', -($slide_image_height - $li_height)/2+'px');
			}
		}
		// Slideshow vertically centralises the slide in the parent li

	});
JS -----





CSS ----
/*------------------------------------*\
    Flexslider - slideshow
\*------------------------------------*/

#slideshow {}
#slideshow.full-width {
    max-height:700px; /* Change height as needed */
    position: relative;
}
#slideshow.full-width .flexslider {
    position: static;
}
#slideshow.full-width .flexslider li {
    max-height: 700px; /* Change height as needed */
    overflow:hidden;
}
#slideshow img {
    width:100%;
    max-width: auto;
}

/*------------------------------------*\
    Flexslider - slideshow
\*------------------------------------*/
CSS ----