When a browser automatically fills form fields, it often applies its own built-in styles. This behavior is common in Chrome, Edge, Opera, Safari, and other Chromium-based browsers.
These autofill styles may override your design by changing the input's background color, text color, and other visual properties. As a result, the appearance of the form can become inconsistent with the rest of the website.
It's important to understand that browsers apply many of these styles through internal user-agent rules, often using !important, which makes them difficult to override with standard CSS.