auto-number-title.css

h1 { counter-reset: h2counter; }
h2 { counter-reset: h3counter; }
h3 { counter-reset: h4counter; }
h4 { counter-reset: h5counter; }
h5 { counter-reset: h6counter; }
h6 { }
h2:before {
  counter-increment: h2counter;
  content: counter(h2counter) ".\0000a0\0000a0";
}
h3:before {
  counter-increment: h3counter;
  content: counter(h2counter) "."
            counter(h3counter) ".\0000a0\0000a0";
}
h4:before {
  counter-increment: h4counter;
  content: counter(h2counter) "."
            counter(h3counter) "."
            counter(h4counter) ".\0000a0\0000a0";
}
h5:before {
  counter-increment: h5counter;
  content: counter(h2counter) "."
            counter(h3counter) "."
            counter(h4counter) "."
            counter(h5counter) ".\0000a0\0000a0";
}
h6:before {
  counter-increment: h6counter;
  content: counter(h2counter) "."
            counter(h3counter) "."
            counter(h4counter) "."
            counter(h5counter) "."
            counter(h6counter) ".\0000a0\0000a0";
}