Tailwind

What is it?

Tailwind is a CSS framwork, its a huge collection of CSS utility classes. Compared to plain CSS it allows you to write less code overall - although unlike bootstrap, Tailwind does not offer prebuilt components.

Does it affect site speed?

It uses Dead Code Elimination, so it eliminates the class styling of those you're not using. Making it load only the relevant styling, resulting in a faster load time.