// Tutorial //

A Brief Intro to CSS Variables (Custom Properties)

Published on June 1, 2016
Default avatar

By Alligator.io

A Brief Intro to CSS Variables (Custom Properties)

While we believe that this content benefits our community, we have not yet thoroughly reviewed it. If you have any suggestions for improvements, please let us know by clicking the “report an issue“ button at the bottom of the tutorial.

Variables in pure CSS without a preprocessor of any kind are available today in most modern browsers. They are officially called custom properties and allow avoiding much of the repetition involved with traditional CSS, and, contrary to variables with preprocessors, they can be changed dynamically.

Here’s how to use custom properties:

/* Declaration */
some-element {
  --my-bg-color: #F9EC31;

/* Using it */
some-element {
  background-color: var(--my-bg-color);

You can also provide a fallback value when using a variable, which will be used if the variable hasn’t been defined:

some-element {
  background-color: var(--my-bg-color, papayawhip);


A common use case is to define variables in the :root pseudo-class and then use it anywhere the value is needed:

:root {
  --funky-shadow: 3px 3px 10px brown;

.ugly-box {
  box-shadow: var(--funky-shadow);


You can also use calc() on variable values:

:root {
  --special-padding: 1.5em;

.pandora-box {
  padding-bottom: calc(var(--special-padding) + 1em);

Browser Support

👉 Myth is a good option to start using CSS variables today.

Can I Use css-variables? Data on support for the css-variables feature across the major browsers from caniuse.com.

span.hljs-number { color: initial; }

Thanks for learning with the DigitalOcean Community. Check out our offerings for compute, storage, networking, and managed databases.

Learn more about us

Want to learn more? Join the DigitalOcean Community!

Join our DigitalOcean community of over a million developers for free! Get help and share knowledge in our Questions & Answers section, find tutorials and tools that will help you grow as a developer and scale your project or business, and subscribe to topics of interest.

Sign up now
About the authors
Default avatar


Still looking for an answer?

Ask a questionSearch for more help

Was this helpful?
Leave a comment
Leave a comment...

This textbox defaults to using Markdown to format your answer.

You can type !ref in this text area to quickly search our full set of tutorials, documentation & marketplace offerings and insert the link!