permalink to single web page

I’ve a sure publish displayed and every publish i click on go to single web page which exhibits extra particulars of the publish. However i’ve completely different templates for the publish particulars which will likely be proven in single web page.

<?php query_posts('post_type=posts&category_name=design'); whereas(have_posts()): the_post(); ?>

<a href="<?php the_permalink(); ?>">Particulars</a>

<?php endwhile; wp_reset_query(); ?>

now in single.php I wish to make a conditon the place the_permalink may move a slug possibly? then i may i embrace the template for design particulars.

Single.php

<?php get_header(); 

 $categorySlugName = single_cat_title(true);

if($categorySlugName == 'design'){

  embrace 'design-details.php';
}    

?>