[dotnet] Apply selenium theme for docs (#17190)

Author: nvborisenko

dotnet/docs/docfx.json

@@ -48,7 +48,8 @@
     "output": "../../build/docs/api/dotnet",
     "template": [
       "default",
-      "modern"
+      "modern",
+      "templates/selenium"
     ],
     "globalMetadata": {
       "_appName": "Selenium .NET API",

dotnet/docs/index.md

@@ -5,5 +5,5 @@ layout: landingPage
 # Welcome to the Selenium .NET API Docs
 
 ## Modules
-- [Selenium.WebDriver](webdriver/OpenQA.Selenium.html)
-- [Selenium.Support](support/OpenQA.Selenium.Support.html)
+- [Selenium.WebDriver](webdriver/OpenQA.Selenium.yml)
+- [Selenium.Support](support/OpenQA.Selenium.Support.yml)

dotnet/docs/templates/selenium/public/main.css

@@ -0,0 +1,8 @@
+:root {
+  --bs-primary: #43b02a;
+  --bs-primary-rgb: 67, 176, 42;
+  --bs-link-color: #43b02a;
+  --bs-link-color-rgb: 67, 176, 42;
+  --bs-link-hover-color: #369022;
+  --bs-link-hover-color-rgb: 54, 144, 34;
+}