You can specify a custom style on the Advanced tab of the Properties panel. You must enter the custom style name.
Use lowercase letters and hyphens to refer to CSS files, classes, and identifiers. Hyphens improve readability, the semantic value of the item, and match the syntax of CSS attributes, for example, margin-left. Avoid articles and conjunctions.
Click Add item.
In the Style Name field, describe the purpose, rather than the style.Specify the primary category of purpose first, as in this example:
custom_is prepended to the class name that you specify.
Define the style in the CSS field. Click the Gear icon to open the Style Editor. You must enter the name
custom_classname on the Advanced tab of the Cell Properties panel to use this custom style.
To delete a custom style, select the style and click the Delete icon.