One way to figure this kind of thing out is to look at other journal examples, some of which can be found here
. Also, a tool like Firebug
really helps with the HTML/CSS modifications, as it can help you find exactly which part of the page you are trying to fix, among other things. As well, you will want to pay attention to the order in which stylesheets are referenced, as each successive stylesheet overrides the previously-called one. In this case, you should have one common.css (or two, if you are using newer versions of OJS), followed by the theme stylesheet, vanilla.css. You probably want to focus on making changes to the header and/or headerTitle ids, and ensure that the changes are made in or added to plugins/themes/vanilla/vanilla.css.