Apply suggestion from @StanFromIreland

Co-authored-by: Stan Ulbrych <stan@python.org>

Author: sepehr-rs

README.md

@@ -22,7 +22,8 @@ To use this theme, add the following to `conf.py`:
 
 - `html_sidebars`, defaults taken from https://www.sphinx-doc.org/en/master/usage/configuration.html#confval-html_sidebars
 
-- `is_rtl` - Enable right-to-left (RTL) layout for languages such as Persian, Arabic, or Hebrew. Code blocks remain left-to-right. Defaults to `"false"`. Set via `html_theme_options = {"is_rtl": "true"}`.
+- To lay pages out right-to-left for languages such as Persian, Arabic, or Hebrew,
+  set `html_theme_options = {"is_rtl": True}`. Defaults to `false`.
 
 ## Translation