💄 Use OS preference theme for docs (#1760)

docs/en/mkdocs.yml

@@ -4,6 +4,7 @@ site_url: https://fastapi.tiangolo.com/
 theme:
   name: material
   palette:
+    scheme: preference
     primary: teal
     accent: amber
   icon:

docs/es/mkdocs.yml

@@ -4,6 +4,7 @@ site_url: https://fastapi.tiangolo.com/es/
 theme:
   name: material
   palette:
+    scheme: preference
     primary: teal
     accent: amber
   icon:

docs/it/mkdocs.yml

@@ -4,6 +4,7 @@ site_url: https://fastapi.tiangolo.com/it/
 theme:
   name: material
   palette:
+    scheme: preference
     primary: teal
     accent: amber
   icon:

docs/pt/mkdocs.yml

@@ -4,6 +4,7 @@ site_url: https://fastapi.tiangolo.com/pt/
 theme:
   name: material
   palette:
+    scheme: preference
     primary: teal
     accent: amber
   icon:

docs/ru/mkdocs.yml

@@ -4,6 +4,7 @@ site_url: https://fastapi.tiangolo.com/ru/
 theme:
   name: material
   palette:
+    scheme: preference
     primary: teal
     accent: amber
   icon:

docs/zh/mkdocs.yml

@@ -4,6 +4,7 @@ site_url: https://fastapi.tiangolo.com/zh/
 theme:
   name: material
   palette:
+    scheme: preference
     primary: teal
     accent: amber
   icon: