You can customize the appearance of both custom subtotals and rows from the data model.

To customize row styles, perform the following 4 steps:

1. Ensure you are in Edit mode.
2. Right-click the row that you want to apply a custom style too and choose “Update row style”.
3. In the editor tools (above the column headers), choose the style and/or format to apply to the style.
4. If you choose any of the custom styles (custom1-4) you might need to go to the Format pane and define their properties. Unless you are using a theme or have already set them up.

Step 1

Step 2

Step 3