Problem

Currently, numbering style in Confluence is as follows

However, some users would like this style to be changed and using a nested number list instead

Diagnosis

This style is not readily available in Confluence. 

Workaround

To implement the style change within a space:

Add the following CSS code on Confluence space Stylesheet.

This workaround includes a customization and might not be compatible with previously implemented customization in Confluence. Please try the following workaround in a test space first.

1. Go to the space that you would like this numbering be implemented on
2. Go to Space Tools > Look and Feel > Stylesheet
3. Edit > copy and paste the following code > Save

ol {
    counter-reset: item;
}
ol li {
    display: block;
    position: relative;
}
ol li:before {
    content: counters(item, ".")".";
    counter-increment: item;
    position: absolute;
    margin-right: 100%;
    right: 10px; /* space between number and text */
}

To implement the style change within a specific list:

Utilize the usage of User Macros.

1. Create a user macro by going to Confluence Admin > User Macros > Create a User Macro. For example:

   Field	Value
   Macro name	nestedlist
   Visibility	Visible to all users in the Macro Browser
   Macro Title	Nested Number List
   Description	Change number list style to nested number list
   Categories	Confluence Content
   Icon URL	You can leave this field blank
   Documentation URL	You can leave this field blank
   Macro body processing	Rendered
   Template	Enter the code below in the template field: ## @noparams <div class="nestedlist">$body</div>

2. Define the CSS for this user macro by going to the space you would like to implement the user macro in > Space Tools > > Look and Feel > Stylesheet

3. Edit > copy and paste the following code > Save

   .nestedlist ol {
       counter-reset: item;
   }
   .nestedlist ol li {
       display: block;
       position: relative;
   }
   .nestedlist ol li:before {
       content: counters(item, ".")".";
       counter-increment: item;
       position: absolute;
       margin-right: 100%;
       right: 10px; /* space between number and text */
   }

4. Now you can add the macro to your Confluence page using the Macro Browser. Number lists entered into the body of the macro placeholder will change its style to numbered nested lists