How to set paragraph margin when editing in CKeditor? I want to make a subtitle on a page, which needs to be centered and to have no space between it and the title.

In the CKeditor window, I entered the subtitle as the first line of text and centered it. In source, CKeditor represented this as:

&lt;p class="rtecenter"&gt;...&lt;/p&gt;


which results in a blank line above. I tried to remove the blank line by changing the above code to:

&lt;br&gt;&lt;center&gt;...&lt;/center&gt;


or just

&lt;center&gt;...&lt;/center&gt;


But CKeditor didn't like either of those. It removed the center tag and replaced the &lt;br&gt; with &lt;p&gt;.
I also tried to add an instruction in CSS as either:

&lt;p class="rtecenter" style="margin-top:0"&gt;...&lt;/p&gt;


or as:

&lt;p class="rtecenter"&gt;&lt;span style="margin-top:0"&gt;...&lt;/style&gt;&lt;/p&gt;


CKeditor also didn't like either of those and just removed the style attribute from the first one and removed the span tag from the second.

I'm not very conversant in CSS, so I'm not sure the above code is properly formed. But the problem is that CKeditor is just removing it so I don't even get a chance to troubleshoot errors in the CSS.

CKeditor seems determined to have that blank line there. How can I get it to let me adjust this spacing between paragraphs (not globally, but on an individual paragraph)?

Thank you.
In your example you have:

&lt;p class="rtecenter"&gt;&lt;span style="margin-top:0"&gt;...&lt;/style&gt;&lt;/p&gt;


I'm assuming that should be:

&lt;p class="rtecenter"&gt;&lt;span style="margin-top:0"&gt;...&lt;/span&gt;&lt;/p&gt;


In general in terms of controlling the space between paragraphs I think the best way to do that is your CSS stylesheet, not really HTML. 

Drupal and CKEditor do some HTML manipulation that you may want to checkout - admin/config/content/ckeditor, then choose your profile and click edit.
Under appearance you can select/deselect some plugins that you might not need.

In terms of a quick fix though I would think that this would work:

&lt;p class="rtecenter" style="margin-top:0; text-align:center;"&gt;...&lt;/p&gt;


But it also depends on what is in your site's stylesheet and your theme.