markdownlint/doc-build/md003.md

This rule is triggered when different heading styles (atx, setext, and 'closed' atx) are used in the same document:

# ATX style H1

## Closed ATX style H2 ##

Setext style H1
===============

Be consistent with the style of heading used in a document:

# ATX style H1

## ATX style H2

The setext_with_atx and setext_with_atx_closed doc styles allow atx-style headings of level 3 or more in documents with setext style headings:

Setext style H1
===============

Setext style H2
---------------

### ATX style H3

Note: the configured heading style can be a specific style to use (atx, atx_closed, setext, setext_with_atx, setext_with_atx_closed), or simply require that the usage is consistent within the document.

Rationale: Consistent formatting makes it easier to understand a document.