Styles are pre-defined combinations of various formatting options that make it easier to keep the presentation of the text uniform. Since a style often contains a number of features at once, when you want to customize the way a text fragment looks, you do not need to change a font, its size, or text and background color separetly.
Define own styles in PKitConfig.xml property global.editor.format
Note: All style classes must start with stages_
<property name="global.editor.format" value="p,h1,h2,h3,p:stages_description_notice, p:stages_description_caption,p:stages_own_style"/>
Define a corresponding style in the custom.css file
p.stages_own_style { font-weight: bold; font-size: 150% }
Define a name of your style in the LocalPKit(_de).properties file
editor.format.p.stages_own_style = My own style
Note: Please define the name in both properties language files.