How can a left and right margin be added to the admin bar without access to “…wp-includes/admin-bar.php”?

If you are using firefox, chrome or safari to browse your site, you can inspect each page’s elements. For example in chrome you can right click anywhere on your browser window and select “inspect element”. Now you should be able to see the code for that page and find out the css classes that the admin bar uses.

For example:

<div id="wpadminbar" class="" role="navigation">
</div>

Once you know what classes to target with css, you can edit your style.css to change those elements. You will need to have some basic css skills. You will also need to use the attribute “!important” in your css to make sure it’s overriding the default wordpress css.