Sass @mixin and @include
Sass Mixins
The @mixin directive lets you create CSS
code that is to be reused throughout the website.
The @include directive is created to let you
use (include) the mixin.
Defining a Mixin
A mixin is defined with the @mixin directive.
Sass @mixin Syntax:
@mixin name {
property: value;
property: value;
...
}
The following example creates a mixin named "important-text":
SCSS Syntax:
@mixin
important-text {
color:
red;
font-size: 25px;
font-weight: bold;
border: 1px solid blue;
}
Tip: A tip on hyphens and underscore in Sass: Hyphens and underscores are considered to be the same. This means that @mixin important-text { } and @mixin important_text { } are considered as the same mixin!
Using a Mixin
The @include directive is used to include a mixin.
Sass @include mixin Syntax:
selector {
@include mixin-name;
}
So, to include the important-text mixin created above:
SCSS Syntax:
.danger {
@include
important-text;
background-color: green;
}
The Sass transpiler will convert the above to normal CSS:
CSS output:
.danger {
color:
red;
font-size: 25px;
font-weight: bold;
border: 1px solid blue;
background-color: green;
}
A mixin can also include other mixins:
SCSS Syntax:
@mixin special-text {
@include
important-text;
@include
link;
@include
special-border;
}
Passing Variables to a Mixin
Mixins accept arguments. This way you can pass variables to a mixin.
Here is how to define a mixin with arguments:
SCSS Syntax:
/* Define mixin with two arguments */
@mixin bordered($color, $width) {
border:
$width solid $color;
}
.myArticle {
@include bordered(blue, 1px);
// Call mixin with two values
}
.myNotes {
@include bordered(red, 2px); // Call mixin with two values
}
Notice that the arguments are set as variables and then used as the values (color and width) of the border property.
After compilation, the CSS will look like this:
Default Values for a Mixin
It is also possible to define default values for mixin variables:
SCSS Syntax:
@mixin bordered($color: blue, $width:
1px) {
border:
$width solid $color;
}
Then, you only need to specify the values that change when you include the mixin:
SCSS Syntax:
.myTips {
@include bordered($color: orange);
}
Using a Mixin For Vendor Prefixes
Another good use of a mixin is for vendor prefixes.
Here is an example for transform:
SCSS Syntax:
@mixin transform($property) {
-webkit-transform: $property;
-ms-transform: $property;
transform: $property;
}
.myBox {
@include transform(rotate(20deg));
}
After compilation, the CSS will look like this:
CSS Output:
.myBox {
-webkit-transform: rotate(20deg);
-ms-transform:
rotate(20deg);
transform: rotate(20deg);
}
