@ckeditor/ckeditor5-ui/theme/globals/_zindex.css

The UI framework and standard UI library of CKEditor 5.

/*
 * Copyright (c) 2003-2025, CKSource Holding sp. z o.o. All rights reserved.
 * For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-licensing-options
 */

:root {
	--ck-z-default: 1;
	--ck-z-panel: calc( var(--ck-z-default) + 999 );
	--ck-z-dialog: 9999;
}