docs: fix the stylesheet name in tutorial (#1260)

Fixes stylesheet name in post `2019-08-09-getting-started.md`

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Co-authored-by: Cotes Chung <11371340+cotes2020@users.noreply.github.com>

Author: dennykorsukewitz

_posts/2019-08-09-getting-started.md

@@ -70,9 +70,9 @@ Social contact options are displayed at the bottom of the sidebar. You can turn
 
 ### Customizing Stylesheet
 
-If you need to customize the stylesheet, copy the theme's `assets/css/style.scss`{: .filepath} to the same path on your Jekyll site, and then add the custom style at the end of it.
+If you need to customize the stylesheet, copy the theme's `assets/css/jekyll-theme-chirpy.scss`{: .filepath} to the same path on your Jekyll site, and then add the custom style at the end of it.
 
-Starting with version `4.1.0`, if you want to overwrite the SASS variables defined in `_sass/addon/variables.scss`{: .filepath}, copy the main sass file `_sass/jekyll-theme-chirpy.scss`{: .filepath} into the `_sass`{: .filepath} directory in your site's source, then create a new file `_sass/variables-hook.scss`{: .filepath} and assign new value.
+Starting with version `6.2.0`, if you want to overwrite the SASS variables defined in `_sass/addon/variables.scss`{: .filepath}, copy the main sass file `_sass/main.scss`{: .filepath} into the `_sass`{: .filepath} directory in your site's source, then create a new file `_sass/variables-hook.scss`{: .filepath} and assign new value.
 
 ### Customing Static Assets