Html ordered list 1.1, 1.2 (Nested counters and scope) not working

I use nested counters and scope to create an ordered list:

ol {
    counter-reset: item;
    padding-left: 10px;
}
li {
    display: block
}
li:before {
    content: counters(item, ".") " ";
    counter-increment: item
}

<ol>
    <li>one</li>
    <li>two</li>
    <ol>
        <li>two.one</li>
        <li>two.two</li>
        <li>two.three</li>
    </ol>
    <li>three</li>
    <ol>
        <li>three.one</li>
        <li>three.two</li>
        <ol>
            <li>three.two.one</li>
            <li>three.two.two</li>
        </ol>
    </ol>
    <li>four</li>
</ol>

I expect the following outcome:

1. one
2. two
  2.1. two.one
  2.2. two.two
  2.3. two.three
3. three
  3.1 three.one
  3.2 three.two
    3.2.1 three.two.one
    3.2.2 three.two.two
4. four

Instead, this is what I see (wrong numbering):

1. one
2. two
  2.1. two.one
  2.2. two.two
  2.3. two.three
2.4 three <!-- this is where it goes wrong, when going back to the parent -->
  2.1 three.one
  2.2 three.two
    2.2.1 three.two.one
    2.2.2 three.two.two
2.3 four

I have no clue, does anyone see where it goes wrong?

Here is a JSFiddle: http://jsfiddle.net/qGCUk/2/

Uncheck "normalize CSS" - http://jsfiddle.net/qGCUk/3/ The CSS reset used in that defaults all list margins and paddings to 0

UPDATE http://jsfiddle.net/qGCUk/4/ - you have to include your sub-lists in your main <li>

ol {
  counter-reset: item
}
li {
  display: block
}
li:before {
  content: counters(item, ".") " ";
  counter-increment: item
}

<ol>
  <li>one</li>
  <li>two
    <ol>
      <li>two.one</li>
      <li>two.two</li>
      <li>two.three</li>
    </ol>
  </li>
  <li>three
    <ol>
      <li>three.one</li>
      <li>three.two
        <ol>
          <li>three.two.one</li>
          <li>three.two.two</li>
        </ol>
      </li>
    </ol>
  </li>
  <li>four</li>
</ol>

Use this style to change only the nested lists:

ol {
	counter-reset: item;
}

ol > li {
	counter-increment: item;
}

ol ol > li {
	display: block;
}

ol ol > li:before {
	content: counters(item, ".") ". ";
	margin-left: -20px;
}

Check this out :

http://jsfiddle.net/PTbGc/

Your issue seems to have been fixed.

---

What shows up for me (under Chrome and Mac OS X)

1. one
2. two
  2.1. two.one
  2.2. two.two
  2.3. two.three
3. three
  3.1 three.one
  3.2 three.two
    3.2.1 three.two.one
    3.2.2 three.two.two
4. four

---

How I did it

Instead of :

<li>Item 1</li>
<li>Item 2</li>
   <ol>
        <li>Subitem 1</li>
        <li>Subitem 2</li>
   </ol>

Do :

<li>Item 1</li>
<li>Item 2
   <ol>
        <li>Subitem 1</li>
        <li>Subitem 2</li>
   </ol>
</li>

This is a great solution! With a few additional CSS rules you can format it just like an MS Word outline list with a hanging first line indent:

OL { 
  counter-reset: item; 
}
LI { 
  display: block; 
}
LI:before { 
  content: counters(item, ".") "."; 
  counter-increment: item; 
  padding-right:10px; 
  margin-left:-20px;
}

Keep it Simple!

This is a Simpler and Standard solution to increment the number and to retain the dot at the end.
Even if you get the CSS right, it will not work if your HTML is not correct. see below.

CSS

ol {
  counter-reset: item;
}
ol li {
  display: block;
}
ol li:before {
  content: counters(item, ". ") ". ";
  counter-increment: item;
}

SASS

ol {
    counter-reset: item;
    li {
        display: block;
        &:before {
            content: counters(item, ". ") ". ";
            counter-increment: item
        }
    }
}

HTML Parent Child

If you add the child make sure it is under the parent li.

Will not work ✘

Notice the parent li and the child ol li are individual here, this will not work.

<ol>
    <li>Parent 1</li> <!-- Parent has open and close li tags -->
    <ol> 
        <li>Child</li>
    </ol>
    <li>Parent 2</li>
</ol>

Will work ✔

You need to place the ol li child element inside parent li. Notice the parent li is hugging the child.

<ol>

    <li>Parent 1 <!-- Parent open li tag -->
        <ol> 
            <li>Child</li>
        </ol>
    </li> <!-- Parent close li tag -->

    <li>Parent 2</li>
</ol>

I encountered similar problem recently. The fix is to set the display property of the li items in the ordered list to list-item, and not display block, and ensure that the display property of ol is not list-item. i.e

li { display: list-item;}

With this, the html parser sees all li as the list item and assign the appropriate value to it, and sees the ol, as an inline-block or block element based on your settings, and doesn't try to assign any count value to it.

Moshe's solution is great but the problem may still exist if you need to put the list inside a div. (read: CSS counter-reset on nested list)

This style could prevent that issue:

ol > li {
    counter-increment: item;
}

ol > li:first-child {
  counter-reset: item;
}

ol ol > li {
    display: block;
}

ol ol > li:before {
    content: counters(item, ".") ". ";
    margin-left: -20px;
}

<ol>
  <li>list not nested in div</li>
</ol>

<hr>

<div>
  <ol>
  <li>nested in div</li>
  <li>two
    <ol>
      <li>two.one</li>
      <li>two.two</li>
      <li>two.three</li>
    </ol>
  </li>
  <li>three
    <ol>
      <li>three.one</li>
      <li>three.two
        <ol>
          <li>three.two.one</li>
          <li>three.two.two</li>
        </ol>
      </li>
    </ol>
  </li>
  <li>four</li>
  </ol>
</div>

You can also set the counter-reset on li:before.

After going through other answers I came up with this, just apply class nested-counter-list to root ol tag:

sass code:

ol.nested-counter-list {
  counter-reset: item;

  li {
    display: block;

    &::before {
      content: counters(item, ".") ". ";
      counter-increment: item;
      font-weight: bold;
    }
  }

  ol {
    counter-reset: item;

    & > li {
      display: block;

      &::before {
        content: counters(item, ".") " ";
        counter-increment: item;
        font-weight: bold;
      }
    }
  }
}

css code:

ol.nested-counter-list {
  counter-reset: item;
}
ol.nested-counter-list li {
  display: block;
}
ol.nested-counter-list li::before {
  content: counters(item, ".") ". ";
  counter-increment: item;
  font-weight: bold;
}
ol.nested-counter-list ol {
  counter-reset: item;
}
ol.nested-counter-list ol > li {
  display: block;
}
ol.nested-counter-list ol > li::before {
  content: counters(item, ".") " ";
  counter-increment: item;
  font-weight: bold;
}

ol.nested-counter-list {
  counter-reset: item;
}

ol.nested-counter-list li {
  display: block;
}

ol.nested-counter-list li::before {
  content: counters(item, ".") ". ";
  counter-increment: item;
  font-weight: bold;
}

ol.nested-counter-list ol {
  counter-reset: item;
}

ol.nested-counter-list ol>li {
  display: block;
}

ol.nested-counter-list ol>li::before {
  content: counters(item, ".") " ";
  counter-increment: item;
  font-weight: bold;
}

<ol class="nested-counter-list">
  <li>one</li>
  <li>two
    <ol>
      <li>two.one</li>
      <li>two.two</li>
      <li>two.three</li>
    </ol>
  </li>
  <li>three
    <ol>
      <li>three.one</li>
      <li>three.two
        <ol>
          <li>three.two.one</li>
          <li>three.two.two</li>
        </ol>
      </li>
    </ol>
  </li>
  <li>four</li>
</ol>

And if you need trailing . at the end of the nested list's counters use this:

ol.nested-counter-list {
  counter-reset: item;
}

ol.nested-counter-list li {
  display: block;
}

ol.nested-counter-list li::before {
  content: counters(item, ".") ". ";
  counter-increment: item;
  font-weight: bold;
}

ol.nested-counter-list ol {
  counter-reset: item;
}

<ol class="nested-counter-list">
  <li>one</li>
  <li>two
    <ol>
      <li>two.one</li>
      <li>two.two</li>
      <li>two.three</li>
    </ol>
  </li>
  <li>three
    <ol>
      <li>three.one</li>
      <li>three.two
        <ol>
          <li>three.two.one</li>
          <li>three.two.two</li>
        </ol>
      </li>
    </ol>
  </li>
  <li>four</li>
</ol>

Thank you everyone above for their answers!

As I needed RTL solution, I found out that this can solve it:

ol.nested-counter-list li {
  display: block;
  unicode-bidi: bidi-override;
}

So you would use any of the solution above, but also update the specific CSS selector for RTL cases.