Hello there, @Cryslove. Currently, the option to change the company color scheme is unavailable in QuickBooks Online (QBO).

However, you can customize templates for your sales forms, such as the font color, size, and style on the Custom Form Styles page.

We understand that having this feature would enhance productivity and help differentiate between multiple companies. We encourage sharing your feedback with us so we can improve the display experience in QuickBooks.

Here's how:     

1. Go to the Gear icon and select Feedback.
2. Enter a brief description of your product suggestion.
3. Click Next to submit it.    

Please leave a reply below if you have further questions. I'll be here to help.