Expanding post box?

Hi(“,)Guys!
I just want some help with regards to my codes. I can’t seem to find a way to expand my post box..wherein my 1 px image will repeat in a y-axis manner with regards to the number of post. Maybe the placement of my div tags is wrong?or maybe something is missing. I hope you can help me guys or show an example(“,).
Here’s my xhtml:

<?php get_header(); ?>

<div id=”postbox-top”> <!– a 15 px top corner with rounded corners –>
</div>

<div id=”postbox-center”> <!– 1px image that will repeat with regards to the number of post –>

<div id=”container”>
<?php if(have_posts()) : ?>

<?php while(have_posts()) : the_post(); ?>

<h2>“title=”<?php the_title(); ?>”><?php the_title(); ?></h2>

<div class=”post” id=”post-<?php the_ID(); ?>”>

<div class=”entry”>

<?php the_content(); ?>

<p class=”postmetadata”>
<?php _e(‘Filed under:’); ?> <?php the_category(‘, ‘) ?> <?php _e(‘by’); ?> <?php the_author(); ?>
<?php comments_popup_link(‘No Comments »’, ‘1 Comment »’, ‘% Comments »’); ?> <?php edit_post_link(‘Edit’, ‘ | ‘, ”); ?>
</p>

</div> <!– entry div end –>

</div> <!– post div end –>

<?php endwhile; ?>

<div class=”navigation”>
<?php posts_nav_link(); ?>
</div>
<?php else : ?>

<div class=”post” id=”post-<?php the_ID(); ?>”>
<h2><?php _e(‘Not Found’); ?></h2>
</div>

<?php endif; ?>

</div> <!– container div end –>

</div> <!– postbox-center div end–>

<div id=”postbox-bottom”> <!– a 15 px bottom corner with rounded corners –>
</div>

<?php get_sidebar(); ?>

<?php include (TEMPLATEPATH . ‘/sidebar2.php’); ?>

<?php include (TEMPLATEPATH . ‘/featured.php’); ?>

<?php include (TEMPLATEPATH . ‘/aboutbox.php’); ?>

<?php get_footer(); ?>

</body>

</div> <!– wrapper div end –>

</html>

and here’s my CSS for the post box:

#postbox-top {
position:absolute;
left:212px;
top:351px;
width:601px;
height:15px;
background:url(images/postbox-top.jpg);
}

#postbox-center {
position:absolute;
left:212px;
top:466px;
width:601px;
height:1px;
background:url(images/postbox-center.jpg);
background-repeat:repeat-y;
}

#postbox-bottom {
position:absolute;
left:212px;
top:625px;
width:601px;
height:15px;
background:url(images/postbox-bottom.jpg);
}