counter-reset is not working on converting from html to docx by cloud convert while it is taking correct number in UI

Question

body {
  font: smaller sans-serif;
    counter-reset: h1 h2;
 }
 h1:before {
    content: counter(h1) ". ";
      counter-increment: h1;
   }
     h1 {
      counter-reset: h2;
     }
    h2:before {
      content: counter(h1) "." counter(h2) ". ";
      counter-increment: h2;
      }



   <h1>Heading</h1>
   <h2>Sub-heading</h2>
    <h2>Sub-heading</h2>
     <h1>Heading</h1>
     <h2>Sub-heading</h2>
        <h2>Sub-heading</h2>

output of docx fileenter image description here

I am trying to convert from html to docx through cloud convert Api but is is missing list numbers seen in SS, Thanks in advanceUI SS