Click the WordPress Toolkit link on the left toolbar.
In the Dashboard section for the selected website, click the Maintenance mode Options icon.
Click the Customize button in the Template section. The File Manager will open in a new browser window. Note: You can change your maintenance page back to the default by clicking the Restore Default button.
Double click the assets and then the images folder.
Click the Upload link. File Upload will open in a new browser window.
Click the Select File button to upload your new image. Tip: You can also drag and drop a file in File Upload. It is recommended to upload a high resolution image.
Click the Go Back to link.
Click the Up One Level link.
Select to highlight the styles.css file.
Click the Edit link.
Then click the Edit button in the confirm dialog. The File Editor will open in a new browser window.
Search for the code line - background: url (images/bg.jpg) no-repeat;
Change bg.jpg to your new image file name that you uploaded. For example, (images/new.jpg).
Click the Save Changes button.
Then confirm by clicking the OK button.
Click the Close button.
If maintenance mode is enabled, click the OK and then Preview button.
If maintenance mode is not enabled, toggle on Maintenance mode and check your website.
Note: If you don't see the new background image, ensure the image file name is correct, and if you're still not seeing it, try clearing your browser cache and refresh the page.