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First, what skin are you using and do you have a link to your site so the problem can be seen?

Here's a link to the site I am working on
http://guysceramicshop.ceramicmold.com/index.php?blog=2&skin=originalb2

It is the space below "12:41:22 pm " and above "This is the first post."

That "andreas01.css" is missing a lot of styling for content elements but one quick way to reduce some of the white space is to find..... and change the line-height:1.6em and change it to 1.0em (or less) as follows

#content {
margin: 0 130px 20px 160px;
border-left: 1px solid #f0f0f0;
border-right: 1px solid #f0f0f0;
padding: 0 10px 0 10px;
line-height: 1.0em;
text-align: left;
}

John,
I changed what you said in andreas01.css. It is easier to see now. The space below "Extended post with no teaser" and above "This is an extended post with no teaser." on the fourth post.

In the Original skin find...

h1, h4, h5, .storyTitle, .storyCategory, .storyAuthor {
	margin:15px 0px 10px 0px;
	padding:0px;
	font-size:28px;
	line-height:28px;
	font-weight:900;
	color:#ccc;
	}

abd edit the margin to suit.... eg

margin:5px 0px;

Hmm, I´m using the custom-skin and after trying a little bit I haven´t found which stylesheet entry exactly I have to modify when increasing the space after the posting headlines.

I think, the following line in _main.php represents the posting headlines, correct?

<h3 class="bTitle"><?php $Item->title(); ?></h3>

But what exaclty do I have to change in the custom.css to increase the space?

Thanks in advance...
Daniel