fixing post width

I’ve been in need for a REALLY simple posting program and am trying out wordpress. basically, the only function I need is the posting function. I don’t need any of the menu’s or anything else, just the posting (it’s going to be inserted into a frames page). I’m having a problem setting the width of the posts though. I’ve searched through dozens of faq’s and forum posts (i don’t have a wp-layout.css file for some reason), but I have yet to find anything that worked. I’ve tried editing the style.css and the index.php file directly, but no go. here’s what i’m trying to do (fix):

http://assassinsdirect.com/

here’s what’s included on my index page:

<div id=”content” class=”narrowcolumn”>
<font face=’arial’ color=’grey’>
<?php if (have_posts()) : ?>
<?php while (have_posts()) : the_post(); ?>

<div class=”post”>
<h2 id=”post-<?php the_ID(); ?>”><?php the_title(); ?></h2>
<small><?php the_time(‘F jS, Y’) ?> <!– by <?php the_author() ?> –></small>

<div class=”entry”>
<?php the_content(‘Read the rest of this entry »’); ?>
</div>

and here’s what’s under that #content section of the style.css:

#content {
font-size: 1.2em
}

.post {
background-color: ffffff;
border: 1px dashed #039;
padding: 10px 10px;
width: 400px;
margin: 0;
}

someone else was working on this before me and deleted a bunch of stuff from either the index.php or style.css file in order to get rid of the menu, header, footer, etc… so i don’t know if he ended up shooting us in the foot by doing that. basically, it’s exactly as we need it now, except for the post width. it looks like its width is set to 100% somewhere, but i can’t find where to override it. i appreciate any help! 🙂