Added examples and definition - CSS (#20066)

* Added examples and definition - CSS

- added two examples with the most used values
- added definition

* Added resources to Graceful Degradation - CSS

Added links to multiple articles / post / explanations / tools to help coders understand the concept

* changed triple backtick to single

* fixed https link

- had to fix one link to point to the https site
- removed one link because it doesn't match with the guide provided by FCC

* Add a space between class name and curly brace

guide/english/css/pointer-events/index.md

@@ -3,9 +3,27 @@ title: Pointer Events
 ---
 ## Pointer Events
 
-This is a stub. <a href='https://github.com/freecodecamp/guides/tree/master/src/pages/css/using-css-transitions/index.md' target='_blank' rel='nofollow'>Help our community expand it</a>.
+This property specifies how your mouse reacts when you hover over any element on a page.
 
-<a href='https://github.com/freecodecamp/guides/blob/master/README.md' target='_blank' rel='nofollow'>This quick style guide will help ensure your pull request gets accepted</a>.
+### Example
+
+```css
+
+.example {
+  pointer-events: auto; 
+  /*this will use the default look set by the browser agent*/
+}
+
+.example {
+  pointer-events: none; 
+  /*this will use the regular mouse look when hovered over the element*/
+}
+
+```
+
+### Other acceptable values
+
+Other values could be: `initial`, and `inherit`
 
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