Posts page is ignoring the css and the template rules

I have a site which can be seen here: Link

The page is set as the posts page, but the posts are ignoring the rules I have set as the width and the scroll of the div. Here is the code of the template page:

<?php if (have_posts()) : while (have_posts()) : the_post(); ?>
<div id="content">
  <div id="meat">
 	<div id="postcontent" class="left">
			<h2><a href="<?php the_permalink() ?>" title="<?php the_title(); ?>" rel="bookmark"><?php the_title(); ?></a></h2>
			<?php echo '<div class="featured-thumbnail">'; the_post_thumbnail(); echo '</div>'; ?> <!-- loades the post's featured thumbnail, requires WordPress 3.0+ -->
				<div id="posttext">
				<?php the_content(__('Read more'));?>
				<p>
					Written on <?php the_time('F j, Y'); ?> at <?php the_time() ?>, by <?php the_author_posts_link() ?>
				</p>
                </div>
    </div>
        <?php endwhile; endif; ?>
    <div id="slideshowarea" class="right">
	<?php echo do_shortcode('[slideshow id=5 w=565 h=520]'); ?>
    </div>
    <div class="clear"></div>
    </div><!--#meat-->

</div><!--#content-->

And the supporting css:

#postcontent {
margin: 0px;
padding: 10px;
width: 539px;
height: 500px;
overflow:auto;
overflow-x: hidden;
background-color: #f7db6d;
}
#slideshowarea {
margin: 0 0 0 0;
padding: 0px;
width: 565px;
overflow:hidden;
}
#posttext{
padding: 0px;
margin:0px;
width: 520px;
overflow: hidden;
}

I cannot get it to work for the life of me. Its literally been bugging me all day. If anyone knows how to do it, let me know.