In WholeCell, your branding colors will appear in the headers of public inventory reports and invoice PDFs.
To set your branding colors, go to 'Settings' on the left side of WholeCell, then choose 'Branding' under 'Sales'.
Input your brand's color codes in HEX format on the Logo Color field and the Text Color field and then hit 'Save'.
Here's mine (a sample inventory report for a customer) from the color codes on the previous screenshot.
This color branding can also be seen on the invoices that you send your customers. Here's a sample invoice from this demo account.