body{counter-reset: section}
h1{counter-reset: sub-section}
h2{counter-reset: composite}
h3{counter-reset: detail}

h1:before{
  counter-increment: section;
  content: counter(section) ".  ";
}
h2:before{
  counter-increment: sub-section;
  content: counter(section) "." counter(sub-section) ".  ";
}
h3:before{
  counter-increment: composite;
  content: counter(section) "." counter(sub-section) "." counter(composite) ".  ";
}
h4:before{
  counter-increment: detail;
  content: counter(section) "." counter(sub-section) "." counter(composite) "." counter(detail) ".  ";
}