wp_admin_css_uri

 * Registers the default admin color schemes.
 *
 * Registers the initial set of eight color schemes in the Profile section
 * of the dashboard which allows for styling the admin menu and toolbar.
 *
 * @see wp_admin_css_color()
 *
 * @since 3.0.0
 */
function register_admin_color_schemes() {
	$suffix  = is_rtl() ? '-rtl' : '';
	$suffix .= SCRIPT_DEBUG ? '' : '.min';

	wp_admin_css_color(
		'fresh',
		_x( 'Default', 'admin color scheme' ),
		false,
		array( '#222', '#333', '#0073aa', '#00a0d2' ),