docs: Move fmt: off docs (#4090)

docs/the_black_code_style/current_style.md

@@ -8,18 +8,9 @@ deliberately limited and rarely added. Previous formatting is taken into account
 little as possible, with rare exceptions like the magic trailing comma. The coding style
 used by _Black_ can be viewed as a strict subset of PEP 8.
 
-_Black_ reformats entire files in place. It doesn't reformat lines that contain
-`# fmt: skip` or blocks that start with `# fmt: off` and end with `# fmt: on`.
-`# fmt: skip` can be mixed with other pragmas/comments either with multiple comments
-(e.g. `# fmt: skip # pylint # noqa`) or as a semicolon separated list (e.g.
-`# fmt: skip; pylint; noqa`). `# fmt: on/off` must be on the same level of indentation
-and in the same block, meaning no unindents beyond the initial indentation level between
-them. It also recognizes [YAPF](https://github.com/google/yapf)'s block comments to the
-same effect, as a courtesy for straddling code.
-
-The rest of this document describes the current formatting style. If you're interested
-in trying out where the style is heading, see [future style](./future_style.md) and try
-running `black --preview`.
+This document describes the current formatting style. If you're interested in trying out
+where the style is heading, see [future style](./future_style.md) and try running
+`black --preview`.
 
 ### How _Black_ wraps lines
 

docs/usage_and_configuration/the_basics.md

@@ -12,7 +12,8 @@ _Black_ is a well-behaved Unix-style command-line tool:
 
 ## Usage
 
-To get started right away with sensible defaults:
+_Black_ will reformat entire files in place. To get started right away with sensible
+defaults:
 
 ```sh
 black {source_file_or_directory}
@@ -24,6 +25,17 @@ You can run _Black_ as a package if running it as a script doesn't work:
 python -m black {source_file_or_directory}
 ```
 
+### Ignoring sections
+
+Black will not reformat lines that contain `# fmt: skip` or blocks that start with
+`# fmt: off` and end with `# fmt: on`. `# fmt: skip` can be mixed with other
+pragmas/comments either with multiple comments (e.g. `# fmt: skip # pylint # noqa`) or
+as a semicolon separated list (e.g. `# fmt: skip; pylint; noqa`). `# fmt: on/off` must
+be on the same level of indentation and in the same block, meaning no unindents beyond
+the initial indentation level between them. Black also recognizes
+[YAPF](https://github.com/google/yapf)'s block comments to the same effect, as a
+courtesy for straddling code.
+
 ### Command line options
 
 The CLI options of _Black_ can be displayed by running `black --help`. All options are
@@ -191,7 +203,7 @@ All done! ✨ 🍰 ✨
 
 Show (or do not show) colored diff. Only applies when `--diff` is given.
 
-### `--line-ranges`
+#### `--line-ranges`
 
 When specified, _Black_ will try its best to only format these lines.