documentation enhancement: better order

Author: benabraham

README.md

@@ -39,12 +39,12 @@ And see the result on `http://localhost:3000/`
 
 To build everything once for production deploy (in `/dist/` folder)
 
-This build uses all generated HTML files for _UnCSS_. If it removes something you need to keep, add and array to `ignore` option in `gulpfile.esm.js`.
-
 ```shell
 npm run build
 ```
 
+This build uses all generated HTML files for _UnCSS_. If it removes something you need to keep, add and array to `ignore` option in `gulpfile.esm.js`.
+
 ## CSS (Sass preprocessor)
 
 `index.css` is compiled from `src/scss/index.scss` by [Sass](http://sass-lang.com/).