switching theme to Material

mkdocs.yml

@@ -2,12 +2,18 @@ site_name: CiviCRM Developer Guide
 repo_url: https://github.com/civicrm/civicrm-dev-docs
 site_description: A guide for CiviCRM developers.
 site_author: The CiviCRM community
-theme: readthedocs
+theme: material
 extra_javascript:
   - js/custom.js
 markdown_extensions:
-  - markdown.extensions.admonition
-  - markdown.extensions.attr_list
+  - attr_list
+  - admonition
+  - codehilite
+  - toc(permalink=true)
+  - pymdownx.superfences
+  - pymdownx.inlinehilite
+  - pymdownx.tilde
+  - pymdownx.betterem
 pages:
 - Home: index.md
 - Basics: