diff --git a/guide/english/certifications/responsive-web-design/basic-css/change-a-variable-for-a-specific-area/index.md b/guide/english/certifications/responsive-web-design/basic-css/change-a-variable-for-a-specific-area/index.md
index 46ac8d488f..e7ae063f00 100644
--- a/guide/english/certifications/responsive-web-design/basic-css/change-a-variable-for-a-specific-area/index.md
+++ b/guide/english/certifications/responsive-web-design/basic-css/change-a-variable-for-a-specific-area/index.md
@@ -3,8 +3,42 @@ title: Change a variable for a specific area
---
## Change a variable for a specific area
-This is a stub. Help our community expand it.
-
-This quick style guide will help ensure your pull request gets accepted.
-
+Cascading CSS variables officially called custom properties are entities which behave similarly to traditional variables. In that variables allow for data to be stored and updated to reflect new values later.
+
+When maintaining complex CSS documents, it is not only beneficial to use CSS Variables but also smart. When making future updates instead of searching potential hundreds of lines of code, one only needs to update the necessary CSS variable.
+
+### Syntax
+
+Declaring the variable:
+
+```css
+--custom-name: value
+```
+
+Using the variable:
+
+```css
+var(--custom-name)
+```
+### Solution
+
+We need to reassign the ```--penguin-belly``` variable to ```white``` in the ```penguin``` class:
+
+```css
+ .penguin {
+ /* add code below */
+ --penguin-belly: white;
+ /* add code above */
+ position: relative;
+ margin: auto;
+ display: block;
+ margin-top: 5%;
+ width: 300px;
+ height: 300px;
+ }
+```
+
+### Sources
+1. [Visit MDN's Cascading CSS Variables page for more information.](https://developer.mozilla.org/en-US/docs/Web/CSS/Using_CSS_variables)
+2. [Perna, Maria Antonietta. "A Practical Guide to CSS Variables (Custom Properties)" *sitepoint*. August 01, 2018. Accessed: October 5, 2018](https://www.sitepoint.com/practical-guide-css-variables-custom-properties/)