Well, this website is implementation in Drupal 12 and, thanks to its brilliant architecture and common "parent" packages such as Symfony and Twig, we know that every page, region, title, block, content parts, form, element down to form element label! and similar does or can have own Twig template. In other words, we do have ability to develop on each or any little part of the render markup, amongst the other powerful things we can do there we can also add existing CSS classes, or groups of classes that Tailwind CSS has ready for us. See more about it - Get started with Tailwind CSS.