Properties Worthy of Mention

Here are some behaviors that are worth mentioning.

1. Custom properties are ordinary properties, so they can be declared on any element.

Declare them on a paragraph element, section, aside, root, or even pseudo-elements. They’ll work as expected.

2. CSS variables are resolved with the normal inheritance and cascade rules

Consider the block of code below:

div {
   --color: red;
div.test {
   color: var(--color)
div.ew {
   color: var(--color)

As with normal variables, the --color value will be inherited by the divs

3. CSS variables can be made conditional with @media and other conditional rules

As with other properties, you can change the value of a css variable within a @media block or other conditional rules.

For example, the following code changes the value of the variable, gutter on larger devices.

:root {
  --gutter: 10px 

@media screen and (min-width: 768px) {
     --gutter: 30px

4. CSS variables can be used in HTML’s style attribute.

You can choose to set the value of your variables inline, and they’ll still work as expected.

<html style="--color: red">

body {   
	color: var(--color)

CSS variables are case sensitive. Be careful with this one. I save myself the stress and write variables in the lower case. Your mileage may vary.

/*these are two different variables*/
:root {
  --color: blue;
 --COLOR: red;

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