Sass Variables
Sass Variables
Variables are a way to store information that you can re-use later.
With Sass, you can store information in variables, like:
- strings
- numbers
- colors
- booleans
- lists
- nulls
Sass uses the $ symbol, followed by a name, to declare variables:
Sass Variable Syntax:
$variablename: value;
The following example declares 4 variables named myFont, myColor, myFontSize, and myWidth. After the variables are declared, you can use the variables wherever you want:
SCSS Syntax:
$myFont: Helvetica, sans-serif;
$myColor: red;
$myFontSize: 18px;
$myWidth: 680px;
body {
font-family: $myFont;
font-size: $myFontSize;
color: $myColor;
}
#container {
width: $myWidth;
}
So, when the Sass file is transpiled, it takes the variables (myFont, myColor, etc.) and outputs normal CSS with the variable values placed in the CSS, like this:
CSS Output:
body {
font-family: Helvetica, sans-serif;
font-size: 18px;
color: red;
}
#container {
width: 680px;
}
Sass Variable Scope
Sass variables are only available at the level of nesting where they are defined.
Look at the following example:
SCSS Syntax:
$myColor: red;
h1 {
$myColor: green;
color: $myColor;
}
p {
color: $myColor;
}
Will the color of the text inside a <p> tag be red or green? It will be red!
The other definition, $myColor: green; is inside the
<h1> rule, and will only
be available there!
So, the CSS output will be:
CSS Output:
h1 {
color: green;
}
p {
color: red;
}
Ok, that is the default behavior for variable scope.
Using Sass !global
The default behavior for variable scope can be overridden by using the
!global switch.
!global indicates that a variable is global,
which means that it is accessible on all levels.
Look at the following example (same as above; but with
!global added):
SCSS Syntax:
$myColor: red;
h1 {
$myColor: green !global;
color: $myColor;
}
p {
color: $myColor;
}
Now the color of the text inside a <p> tag will be green!
So, the CSS output will be:
CSS Output:
h1 {
color: green;
}
p {
color: green;
}
Tip: Global variables should be defined outside any rules. It could be wise to define all global variables in its own file, named "_globals.scss", and include the file with the @include keyword.
