What Is SCSS and How To Use It?

SCSS (Sassy CSS) is a powerful extension to CSS, allowing you to write cleaner, more modular, and maintainable stylesheets. SCSS can reduce your coding time and increase the maintainability of code, although it requires an additional step to compile the code into CSS. In this guide, you’ll learn the key differences between SCSS and CSS, how to use SCSS in your projects, and how to convert SCSS into CSS.

In this section, we’ll cover the following topics:

What is SCSS and How Does It Differ from CSS?

SCSS (Sassy CSS) is a CSS preprocessor. SCSS enhances CSS by adding programming-like capabilities, which allow for more structured and scalable stylesheets. Using SCSS, you can obtain the following benefits:

• Handling variables more efficiently
• Utilizing nesting code structure
• Creating code components using mixins

To enjoy these benefits, you need additional set-ups to compile SCSS. Let’s explore each benefit in more detail.

Handling variables more efficiently

In SCSS, variables allow you to store values that you can reuse throughout your stylesheet, such as colors, font sizes, or any repeated value. This feature is also available in modern CSS, but SCSS variables differ in that they are static and scoped, meaning they don’t inherit across elements like CSS custom properties.

Here’s an example of SCSS variables:

$primary-color: #3498db;
$font-size: 16px;

body {
  background-color: $primary-color;
  font-size: $font-size;
}

When compiled into CSS, the output would be:

body {
  background-color: #3498db;
  font-size: 16px;
}

In CSS, you can achieve something similar with custom properties, but SCSS variables provide a more consistent way to manage values throughout the stylesheet without concern for inheritance.

Utilizing nesting code structure

Nesting in SCSS allows you to write code that mimics the structure of your HTML. This makes your stylesheets easier to read and maintain, especially for deeply nested elements. Let’s compare how SCSS and CSS handle nested structures.

SCSS example:

nav {
  ul {
    list-style: none;
    li {
      display: inline-block;
      a {
        text-decoration: none;
        color: $primary-color;
      }
    }
  }
}

The compiled CSS would look like this:

nav ul {
  list-style: none;
}

nav ul li {
  display: inline-block;
}

nav ul li a {
  text-decoration: none;
  color: #3498db;
}

Without nesting, you would need to write all of these selectors separately in CSS, which increases redundancy and makes the code harder to follow.

Creating code components using mixins

A mixin in SCSS allows you to create reusable chunks of CSS. You can think of mixins as functions that let you pass arguments and apply styles in multiple places without duplicating code. In CSS, there’s no native support for mixins, so you would have to copy and paste code repeatedly.

SCSS example with mixin:

@mixin flex-center {
  display: flex;
  justify-content: center;
  align-items: center;
}

.container {
  @include flex-center;
  height: 100vh;
}

The compiled CSS would look like this:

.container {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
}

By using mixins, you avoid code duplication and can easily update multiple elements by modifying a single mixin.

Converting SCSS to CSS

Browsers understand only standard CSS, not SCSS syntax. SCSS, a preprocessor scripting language, allows for more efficient styling by enabling variables, nesting, and modular code. However, for these styles to display correctly, SCSS files must be compiled into regular CSS. This conversion process ensures that all web browsers can read and render styles consistently.

There are several ways to convert SCSS into CSS:

Approach 1: Manual Conversion via Command Line

To convert SCSS into CSS manually, you need to have a Sass compiler installed on your machine. This is often done using Node.js, which allows you to run Sass as a command-line tool. If Sass is installed, run the following command:

sass scss/style.scss css/style.css

Approach 2: Automated Conversion with Build Tools (Gulp, Webpack, etc.)

For larger projects, you can use build tools like Gulp or Webpack to automatically convert SCSS to CSS whenever you make changes. This eliminates the need for manual compilation.

Approach 3: Using a SCSS to CSS Converter

There are also online tools available for quick conversions, which can be handy for small projects or one-off tasks.

Step-By-Step Guide to Using SCSS

In this guide, we will use Visual Studio Code to demonstrate how to set up SCSS and convert it into CSS for your projects.

Install Node.js and Sass

First, you need to install Node.js to run Sass. Once Node.js is installed, you can use npm (Node Package Manager) to install Sass globally on your machine:

npm install -g sass

Set Up a Project Folder

Create a project folder with separate directories for SCSS and CSS files. Here’s an example structure:

/your-project-folder/
   ├── scss/
       └── style.scss
   ├── css/
       └── style.css

Write Your SCSS Code

Inside the /scss/ folder, create a file called style.scss. Write your SCSS code in this file. Here’s an example:

$primary-color: #3498db;

body {
  background-color: $primary-color;
}

Compile SCSS to CSS

Use the Built-in Terminal (Manual Approach)

You can manually compile SCSS to CSS using the terminal in Visual Studio Code. Open the terminal and run:

sass scss/style.scss css/style.css

Automate the Compilation with Extensions

For a more automated approach, use the Live Sass Compiler extension in Visual Studio Code. This extension automatically compiles SCSS to CSS every time you save your .scss file.

Configure Live Sass Compiler for Advanced Users

You can configure the Live Sass Compiler to output both regular and minified CSS files, or to specify custom output directories. Open VS Code’s settings and add the following to your settings.json file:

"liveSassCompile.settings.formats": [
 {
   "format": "expanded",
   "extensionName": ".css",
   "savePath": "/css"
 },
 {
   "format": "compressed",
   "extensionName": ".min.css",
   "savePath": "/css"
 }
]

Using AI-Powered Tools for SCSS

With the rise of AI tools, you can simplify the process of generating and converting SCSS code using AI-powered tools like ChatGPT. These tools allow you to write SCSS more efficiently and convert SCSS to CSS automatically.

/your-project-folder/
    ├── 07-03-what-is-scss/ 
        ├── css/example.css
        ├── scss/example.scss
        ├── example.html

AI Case 1: Generating SCSS Code

Sample AI prompt:

Sample code output:

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <link rel="stylesheet" href="css/example.css" />
    <title>SCSS Example</title>
  </head>
  <body>
    <h1>Hello, SCSS!</h1>
  </body>
</html>

$primary-color: lightblue;

body {
  background-color: $primary-color;
  text-align: center;
}

Save the HTML code above in example.html and the SCSS code in scss/example.scss in the 07-03-what-is-scss folder.

You’ll see the result in your browser after converting SCSS code into CSS code in the next case.

AI Case 2: Quick Conversion of SCSS into CSS

Sample AI prompt:

Sample code output:

body {
  background-color: lightblue;
  text-align: center;
}

Instructions to see the results:

1. Save the code above in example.css in the 07-03-what-is-scss/css/ folder.
2. Open example.html in your browser to view the webpage with a light blue background and centered text.

Visit this link to see how it looks in your web browser:
Demo Web Page 114

AI Case 3: Quick Conversion of CSS into SCSS

Sample AI prompt:

Sample code output:

$primary-color: lightblue;

body {
  background-color: $primary-color;
  text-align: center;
}

You will see the same code as generated in Case 1.

Best Practices for Using SCSS

SCSS enables the creation of more organized, maintainable, and scalable stylesheets. Here are some best practices to follow:

• Use Variables for Consistency: Define variables for colors, fonts, and other repeated values. This reduces redundancy and makes global updates simpler and more consistent.
• Leverage Nesting Carefully: Use nesting to mirror HTML structure and simplify selectors, but avoid deep nesting to prevent overly complex code and CSS specificity issues.
• Create Reusable Mixins: Write mixins for reusable styles or patterns like flex layouts. This practice promotes code reuse and simplifies style updates.
• Modularize with Partial Files: Break your SCSS into partials (small, focused files) for easier maintenance. Use @import to compile them into a single stylesheet.
• Optimize with Functions: Use SCSS functions for repetitive tasks, such as calculating colors or converting units, to simplify code and make it more dynamic.
• Minimize CSS Output: Avoid unnecessary code that may bloat your CSS output by organizing and optimizing your SCSS files.
• Automate Compilation: Use tools like Live Sass Compiler in VS Code or task runners to automatically compile SCSS to CSS, reducing manual tasks and improving workflow efficiency.

By following these practices, you’ll ensure that your SCSS is clean, efficient, and easy to maintain.