admin_body_class │ filter-hook │ WP 2.3.0

Allows you to add custom CSS classes to the body tag in the site's admin panel.

This filter differs from post_class and body_class as follows:

  1. $classes is a space-separated string of CSS classes instead of an array.
  2. Core classes such as wp-admin, wp-core-ui, no-js, and others cannot be changed.

Usage

add_filter( 'admin_body_class', 'wp_kama_admin_body_class_filter' );

/**
 * Function for `admin_body_class` filter-hook.
 * 
 * @param string $classes Space-separated list of CSS classes.
 *
 * @return string
 */
function wp_kama_admin_body_class_filter( $classes ){

	// filter...
	return $classes;
}
$classes(string)
Space-separated CSS classes.

Examples

#1 Add custom classes to the <body> tag in the admin area

## Add custom classes to the `<body>` tag in the admin area
add_action( 'admin_body_class', 'add_my_class' );
function add_my_class( $classes ){
	$my_class = 'my-css-1 my-css-2';
	return $classes ? $classes . ' ' . $my_class : $my_class;
}

Changelog

Since 2.3.0 Introduced.

Where the hook is called

In file: /wp-admin/admin-header.php
admin_body_class
wp-admin/admin-header.php 252 
$admin_body_classes = apply_filters( 'admin_body_class', '' );
wp-admin/includes/template.php 2190 
$admin_body_classes = apply_filters( 'admin_body_class', '' );

Where the hook is used in WordPress

wp-admin/includes/class-wp-site-health.php 51 
add_filter( 'admin_body_class', array( $this, 'admin_body_class' ) );
wp-admin/nav-menus.php 689 
add_filter( 'admin_body_class', 'wp_nav_menu_max_depth' );
wp-admin/widgets-form.php 23 
add_filter( 'admin_body_class', 'wp_widgets_access_body_class' );