You’ve poured your heart into your manuscript. But when you preview the ePub, the formatting is a mess: images overflow, headings vanish from the navigation, and text becomes unreadable on a phone. For self-publishers, ensuring a perfect reading experience across every device is the final, frustrating hurdle. The core principle for success is device-agnostic styling . Your eBook is not a printed PDF; it’s a reflowable document that must adapt gracefully to screens from a 6-inch e-reader to a 27-inch monitor. AI automation excels at applying and validating the CSS rules that make this possible, but you must guide it with the right framework. Consider this mini-scenario: You ask an AI, "Format my chapter headings." Without context, it might use fixed px units. But with the principle of device-agnostic styling, you guide it to use relative rem units and semantic HTML tags, ensuring consistency everywhere. Here is how to implement this with AI assistance: Command with Semantic Intent.…