I want to ensure this will be taken care of, @queencitypi.

In QuickBooks Online (QBO), when choosing black as the color for the template theme, the header line of the table will appear gray. This is because the color of the main text (amount, date, etc.) will also become black. This way, the titles are still visible. Please refer to the screenshot for reference: 

In the meantime, you'll want to design and upload custom form styles for your invoices. 

Also, to request the addition of a new option when applying colors to your invoice template, I'd recommend submitting feedback to our product engineers. Rest assured that they are bound to enhance the software's capacity to meet your business needs. Here's how:

1. In your QBO program, click the Gear or Settings icon.
2. Next, select Feedback.
3. Then, enter your product suggestion. Example: Have an option to print the customized invoice template in black rather than part black part gray after selecting the Black color under the Design tab.
4. Once done, select Next to submit.

To monitor and track the submitted feedback, I'd recommend visiting our QuickBooks Online Feature Requests website. From there, you can also add a vote to another product request that you think will be a big help in optimizing your QBO navigation.

In case you need helpful articles and links to guide you in your QBO tasks, please visit our QuickBooks Help Articles page.

Add a reply below if you have any other concerns about customizing your invoice templates. I got your back. Keep safe always.