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. Alternatively you can specify a css style name in Format Colunn Predefined Config (which you must provide).
This example has 2 Format Columns: The Order Id column is lime green with a red fore colour, and the Order Date column is italicised with a smaller font.