Using CSS in your web design has many benefits. In addition to being easy to use, it's better for SEO than using HTML alone. With CSS, you can improve your ranking on the search results page and attract web crawlers to your website.

Is internal CSS bad for SEO?

Inline CSS and scripts are not ranking factors for Google. The only time that code matters for SEO would be if it impacts performance. For SEO, your page source code must download completely with 7 seconds. If it is slower than that for Googlebot, Google makes rankings worse for it.

Does Google look at CSS?

Google has whole teams of people that monitor this sort of activity and develop algorithms to detect it. So the technical answer is YES, search engines DO understand CSS.