Andrei Lupu

<p>You can use this plugin to add a unique CSS class to your pages or posts.</p>
<h4>Demo</h4>
<p><a href="https://tastewp.com/" rel="nofollow ugc">TasteWP</a> has prepared a quick WordPress instance with this plugin, so you can give it a try <a href="https://demo.tastewp.com/wp-custom-body-class" rel="nofollow ugc">in this demo</a></p>
<h4>Responsiveness</h4>
<p>There’s a way to add a class to appear only on mobile devices. You can do that by simply adding <code>mobile-</code> on the front of<br />
the class. For example, if you want to have the class “car” for mobile side, you need to use “mobile-car”.</p>
<h4>Support me</h4>
<p>If you find this plugin helpful, or you just want to send me a coffee here are the ways:</p>
<ul>
<li>Use the Github Sponsor button</li>
<li><a href="https://ko-fi.com/thelup" rel="nofollow ugc">Ko-fi</a></li>
<li>Watch me coding on <a href="https://www.twitch.tv/thelup/" rel="nofollow ugc">twitch.tv/thelup</a></li>
<li>Or simply visit my site <a href="https://a.lup.dev/" rel="nofollow ugc">lup.dev</a> and make those analytics ring the bells.</li>
</ul>


Custom Body Class

A plain simple plugin which allows you to add a custom CSS class the HTML body tag.

Edward Caissie

<p>Simple plugin that adds classes to the <code>body_class</code> output upon activation, including: a full list of date related classes; a few holiday classes; and, a generic sample full calendar extension.</p>
<h4>Copyright 2012-2015  Edward Caissie  (email : edward.caissie@gmail.com)</h4>
<p>This program is free software; you can redistribute it and/or modify<br />
  it under the terms of the GNU General Public License version 2,<br />
  as published by the Free Software Foundation.</p>
<p>You may NOT assume that you can use any other version of the GPL.</p>
<p>This program is distributed in the hope that it will be useful,<br />
  but WITHOUT ANY WARRANTY; without even the implied warranty of<br />
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the<br />
  GNU General Public License for more details.</p>
<p>You should have received a copy of the GNU General Public License<br />
  along with this program; if not, write to the Free Software<br />
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA</p>
<p>The license for this software can also likely be found here:<br />
  http://www.gnu.org/licenses/gpl-2.0.html</p>


BNS Body Classes

Simple plugin that adds classes to the body_class output upon activation, including a range of date related classes.

Custom Body Class vs BNS Body Classes