Aaron T. Grogg

When in Admin mode, this plug-in adds classes to the <code><body></code> tag to let 
your CSS know where you are.
For example, if you are viewing the list of all your Posts, you would get this additional class: 
 edit-list-post 
And, when you are editing a Post, something like this: 
 edit-page-post
Alternatively, for custom posts, for example “movie”, you would see either: 
 edit-list-movie 
or: 
 edit-page-movie
This allows you to write custom CSS and JS to interact with these varying edit pages within WP.
Please let me know if you have any questions/suggestions/thoughts, 
Atg

Add Custom Post Type Slugs to Admin Body Class

Add Custom Post Type Slugs to Admin &lt;body&gt; Class

Anil Ankola

This is a really simple way to add body class and is especially useful if you are creating a theme or website.

Add Custom Body Class

Use this plugin to add a custom class in the HTML body tag.

Add Custom Post Type Slugs to Admin Body Class vs Add Custom Body Class