[verisimilidude]

Yes, you can use Tailwind utility classes within your own CSS files. The Tailwind syntax for creating custom classes is @apply. Here's how they recommend approaching the problem.

https://tailwindcss.com/docs/extracting-components

I find @apply useful for styling HTML that I don't directly control, such as rendered Markdown. Otherwise, I do prefer Tailwind's suggestion to use templates/components instead of custom classes, wherever it makes sense.