Target last child..why it doesn't working

Hi,
I want to target last child of an element inside a while loop.
this is the code:

<div class="col-sm-4">
				<?php if ( $the_query->have_posts() ): ?>
					<?php while ( $the_query->have_posts() ) : $the_query->the_post(); ?>
							<h2 class="special-project-title"><?php the_title()?></h2> <br/>
							<div class="post-meta special-project-meta"><?php mida_post_meta()?></div><br/>
							<a class="more-link spaciel-project-more" href="<?php echo the_permalink() ?>"><?php echo __('Read More', 'mida')?></a><br/>
					<?php endwhile; endif;?>
					<?php wp_reset_query(); ?>
</div>

CSS:

.spaciel-project-more{
	border-bottom: 1px solid black;
	margin-top: -15px;
	margin-bottom: -15px;
    padding-bottom: 15px;
}
.spaciel-project-more:last-child{
	border-bottom:none;
}

I want in the last “read more” element to disable the border bottom, but it doesnt work.. any help? thanks!