CSS not applying to Sub category pages

Hi there

Can anyone help with this issue I have where the category specific Stylesheet does not get applied to a sub page which sits on a single.php

The dev site is here

I’m building a blog, shop and news page on a site which all run on the Posts of a wordpress install.

Each needs slightly different layout and styles/colours applied to it, hence the different stylesheets.

In the head I have:

<link rel="stylesheet" type="text/css" href="<?php bloginfo('stylesheet_url'); ?>" />

<?php if ( is_category('news')) { ?>
<link rel="stylesheet" href="<?php bloginfo('stylesheet_directory'); ?>/styles/news.css" type="text/css" media="screen" />
<?php } ?>
<?php if ( is_page('about')) { ?>
<link rel="stylesheet" href="<?php bloginfo('stylesheet_directory'); ?>/styles/about.css" type="text/css" media="screen" />
<?php } ?>
<?php if ( is_category('people')) { ?>
<link rel="stylesheet" href="<?php bloginfo('stylesheet_directory'); ?>/styles/people.css" type="text/css" media="screen" />
<?php } ?>
<?php if ( is_category('shop')) { ?>
<link rel="stylesheet" href="<?php bloginfo('stylesheet_directory'); ?>/styles/shop.css" type="text/css" media="screen" />
<?php } ?>
<?php if ( is_page('submit')) { ?>
<link rel="stylesheet" href="<?php bloginfo('stylesheet_directory'); ?>/styles/submit.css" type="text/css" media="screen" />
<?php } ?>
<?php if ( is_page('crits')) { ?>
<link rel="stylesheet" href="<?php bloginfo('stylesheet_directory'); ?>/styles/crits.css" type="text/css" media="screen" />
<?php } ?>
<?php if ( is_category('blog')) { ?>
<link rel="stylesheet" href="<?php bloginfo('stylesheet_directory'); ?>/styles/blog.css" type="text/css" media="screen" />
<?php } ?>
<?php if ( is_page('say-hi')) { ?>
<link rel="stylesheet" href="<?php bloginfo('stylesheet_directory'); ?>/styles/say-hi.css" type="text/css" media="screen" />
<?php } ?>

The individual category pages for each section need to be different and I pull the 3 different loops in as templates:

<?php
$post = $wp_query->post;
if ( is_category('3') ) {
include(TEMPLATEPATH . '/loop-news.php');
} elseif ( is_category('5') ) {
include(TEMPLATEPATH . '/loop-blog.php');
} elseif ( is_category('9') ) {
include(TEMPLATEPATH . '/loop-shop.php');
} else {
include(TEMPLATEPATH . '/loop-people.php');
}
?>

And then on single.php I use:

<?php
$post = $wp_query->post;
if ( in_category('3') ) {
include(TEMPLATEPATH . '/single2.php');
} elseif ( in_category('5') ) {
include(TEMPLATEPATH . '/single1.php');
} elseif ( in_category('9') ) {
include(TEMPLATEPATH . '/single3.php');
} else {
include(TEMPLATEPATH . '/single4.php');
}
?>

These styles apply perfectly to the category page for each, however if I drill down to a page that uses the single template it doesn’t apply the stylesheet.

I’m sure it was working before I started work on the ‘shop’ category and it was only after changing the statement to an ‘elseif’ statement from an ‘if else statement’ on single.php that I got issues.

Any help to my garbled message would be appreciated
Thanks in advance
John