To modify the color, font, size, style, background color, and other caption settings on your Xbox One, please follow the steps below:

1. Press the Xbox button on your remote to open the guide.
2. Select Settings.
3. Select All Settings.
4. Under Ease of Access, select Closed captions.
5. Here you can turn closed captions on and off and set a custom style.

Style options for closed captions include:

Font
- Caption color
- Caption transparency
- Caption size
- Caption style
- Caption effect

Background and window
- Background color
- Background transparency
- Window color
- Window transparency