theme/heading.css
/*
* Copyright (c) 2003-2020, CKSource - Frederico Knabben. All rights reserved.
* For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-oss-license
*/
.ck.ck-heading_heading1 {
font-size: 20px;
}
.ck.ck-heading_heading2 {
font-size: 17px;
}
.ck.ck-heading_heading3 {
font-size: 14px;
}
.ck[class*="ck-heading_heading"] {
font-weight: bold;
}