JSFiddle - React, Tailwind, and code Playground

HTML

<ol>
  <li>Раздел 6 | Правила общения в любых чатах
    <ol>
      <li>Мафия (вся).
        <ol>
          <li id="">Lorem ipsum dolor sit amet consectetur adipisicing elit. Eligendi nulla, eaque qui ipsam eos asperiores, impedit eveniet rem omnis consequuntur!</li>
          <li id="">Lorem ipsum dolor sit amet consectetur adipisicing elit. Eligendi nulla, eaque qui ipsam eos asperiores, impedit eveniet rem omnis consequuntur!</li>
          <li id="">Lorem ipsum dolor sit amet consectetur adipisicing elit. Eligendi nulla, eaque qui ipsam eos asperiores, impedit eveniet rem omnis consequuntur!</li>
        </ol>
      </li>
      <li>Госслужащие.

        <ol>
          <li id="">Lorem ipsum dolor sit amet consectetur adipisicing elit. Eligendi nulla, eaque qui ipsam eos asperiores, impedit eveniet rem omnis consequuntur!</li>
          <li id="">Lorem ipsum dolor sit amet consectetur adipisicing elit. Eligendi nulla, eaque qui ipsam eos asperiores, impedit eveniet rem omnis consequuntur!</li>
          <li id="">Lorem ipsum dolor sit amet consectetur adipisicing elit. Eligendi nulla, eaque qui ipsam eos asperiores, impedit eveniet rem omnis consequuntur!</li>
        </ol>
      </li>
    </ol>
  </li>
</ol>

CSS

OL {
  counter-reset: item
}

LI {
  display: block
}

LI:before {
  content: counters(item, ".") " - ";
  counter-increment: item
}