Format Column allow you to style an entire column. Unlike Conditional Styles, the Format Column style is always applied, irrespective of the data in the cell.
Format Columns are created using the same Style builder as Quick Search and Conditional Styles, which allows you to name key elements of the style.
Alternatively you can specify a css style name in Format Colunn Predefined Config (which you must provide in your css).
This example has 2 Format Columns: The Order Id column is lime green with a red fore colour, and the Order Date column is bold and italicised and with a smaller font.