Website Builder Version 8
Simply click on the row you want to edit, and this will open the Row Design menu, where you can change the background in the style section; changing the row colour, setting the background as an image, or inserting a video background.
Website Builder Version 7
First you must ensure that Row/Column editing is enabled by clicking on the Row/Column editing button at the top of the page. You will receive a notification that you have enabled this.
When you hover over the row you wish to edit, a small overlay will appear. Click the Cog icon to open the settings panel.
Once the panel opens, you can give the zone one of the predefined styles from the theme, or create your own by clicking on the Plus icon.
Name your new style, then click Add Row Style.
You can now customise your new style, including changing the background. Once complete, click the Save changes button to save your new style. You will now be able to apply this style to other zones on your website.