I like tailwind too but it's not an alternative to learning CSS. You still need to know CSS to be able to use tailwind
For my own homepage i did not write a single line of css.
I am very, very bad with CSS and can't wrap my head around it, but tailwind allowed me to create a very pretty, responsive homepage with very high lighthouse scores (bought tailwind UI too).
Congrats, you now know CSS! It sounds like I'm joking but honestly, Tailwind is essentially composable shorthand for CSS with a design system applied. If you grok Tailwind, you understand the concepts of CSS, you just might not know the full names for all the properties and values.
I do unterstand the basic ideas behind CSS, but is just cant apply it. Tailwind allowed me to apply it.
If i could, i would prefer to write CSS! After 10 years i have given up though.
Personal anecdote, I understood how flexbox works only after using Tailwind for a personal project.