Need Help : Thumb image css not recognized

Hi Guys

i am trying to pull thumb image from my own function

# Displays post image attachment (sizes: thumbnail, medium, full)
function dp_attachment_image($postid=0, $size='thumbnail', $attributes='') {
if ($postid<1) $postid = get_the_ID();
if ($images = get_children(array(
'post_parent' => $postid,
'post_type' => 'attachment',
'numberposts' => 1,
'post_mime_type' => 'image',)))
foreach($images as $image) {
$attachment=wp_get_attachment_image_src($image->ID, $size);
?><img src="<?php echo $attachment[0]; ?>" <?php echo $attributes; ?> /><?php
}
}

well i am able to pull the thumb image but it don’t recognized img css

here is my code syntax

<div class="home-squares">
<div class="home-headings">Random Articles</div>
<?php $my_query = new WP_Query('orderby=rand&showposts=2');
while ($my_query->have_posts()) : $my_query->the_post();
?>
<div class="random">
<div class="random-image">
<a href="<?php the_permalink() ?>"><?php dp_attachment_image($post->ID, 'thumbnail', 'alt="' . $post->post_title . '"'); ?></a>

</div>
<div class="random-content">
<a href="<a href="<?php the_permalink(); ?>"><?php the_title(); ?></a>
<p><?php echo dp_clean($post->post_content, 80); ?></p>
</div>
</div>
<?php endwhile; ?>
</div>
<!--End Random Articles-->

My css

/**** Begain Random box **/

.home-squares {
background-color: #FFFFFF;
width: 280px;
display: block;
padding: 10px;
border: 1px solid #EBEBEB;
float: left;
margin-right: 12px;
margin-top: 10px;
margin-bottom: 10px;
}

.random-image {
width: 70px;
height: 80px;
border: 5px solid #F8F4E0;
float: left;
}

.random-image .img {width: 70px;
height: 80px;
	;
}
.random-content {
float: right;
width: 190px;

}
.random {
width: 280px;
float: left;
margin-top: 10px;
}
.home-headings {
height: 27px;
border: 1px solid #DDD7B3;
background-color: #F4EFD2;
background-image: url(images/heading-bg.gif);
width: 268px;
color: #575447;
font-size: 13px;
font-weight: bold;
padding-left: 10px;
padding-top: 8px;
}

well i don’t want to pull via custom field

Looking forward for your help