By default ag-Grid will display according to the provided theme you use (e.g. Balham, Blue, Blue etc.)
However you are able to style the rows in the ag-Grid using the RowStyles property of User Interface State.
The RowStyles array can include 'Odd' and 'Even' properties which will style as their names suggest; you can provide just one of these properties but typicallly both will be supplied.
Alternatively you can provide an 'All' property. This will style all rows (and will ignore the Even and Odd properties if they are also supplied).
Each of the 3 types of properties will use an Adaptable Style object - this can either include a list of style values (e.g. 'ForeColor') or a cssClass name (which you must then provide in your css).
In this example we have set an Even Row style (using a classname property) and an Odd Row Style that uses the AdaptableStyle object.