The problem is that it may take 2 seconds of CSS, but it is a software change that then requires the product to be revalidated, along with the matching paperwor

The problem is that it may take 2 seconds of CSS, but it is a software change that then requires the product to be revalidated, along with the matching paperwork (functional design doc, software design, technical design, customer support documentation and training material) and validation evidence to be submitted to your official document control system. And this process can take days, weeks, or months, depending on how complicated (due to extreme CYA) your compliance department makes the process. And the company compliance folks want to go overboard as they want to make sure the FDA auditors are happy the next time there is a surprise audit.