What does var in css mean?

The var() function in CSS provides variable storage and usage functions. Values ​​can be assigned to variables and used throughout the style sheet. Usage: 1. Use the -- prefix to declare the variable (--: ); 2. Use the var() function to obtain the variable value (var(--) ). Use var() for reusability, consistency, and ease of maintenance, and to create values ​​that adjust based on media queries or JavaScript variables.

#What is var in CSS?

The var() function in CSS allows you to store and use variables. It lets you assign a value to a variable and then reuse that variable throughout your stylesheet.

How to use var

To use var(), follow these steps:

1. Declare a variable : Use the -- prefix to declare a CSS variable. The syntax is: --<variable name>: <value>;</value></variable>
2. Use variables: Use the var() function to get the value of the variable. The syntax is: var(--<variable name>);</variable>

Example

For example, the following code declares a A variable named --primary-color and set it to blue:

:root {
  --primary-color: blue;
}

You can then use this variable in other parts of the style sheet:

.heading {
  color: var(--primary-color);
}

Advantages

There are many advantages to using CSS variables, including:

• Reusability:You can easily use variables on multiple elements, thereby reducing code duplication.
• Consistency: Variables help maintain style guides by ensuring values ​​are consistent throughout the stylesheet.
• Easy to maintain: If you need to change the value of a variable, you only need to make the change once in the declaration.
• Dynamic values: You can use the var() function to create dynamic values, such as resizing or coloring based on media queries or JavaScript variables.

Note

• Variables must be declared before the element to be used.
• You can use nested variables, such as var(--var-1).
• var() The function does not support calculation expressions, such as var(--var-1 var(--var-2)).

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