Dedicated Dark Mode - mods or workarounds?

Hi! As someone with severe neurological issues and light sensitivity, I'm struggling to work with Reader more than a few minutes at a time. The "dark mode" option seems to only affect the UI and not the document itself. And the accessibility feature is so broken as to be unusable - it cannot be turned on and off for different documents, and depending on the formatting, many documents are rendered altogether unreadable. I'm desperate for a solution for my editing and proofreading work, which factors in document formatting and colours. Do things like mods and plugins exist for Adobe products? And if so, might anyone know of a plugin or workaround I can use to darken the backgrounds of documents and save my eyes?