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Parent Selector

The parent selector, &, is a special selector invented by Sass that’s used in nested selectors to refer to the outer selector. It makes it possible to re-use the outer selector in more complex ways, like adding a pseudo-class or adding a selector before the parent.

When a parent selector is used in an inner selector, it’s replaced with the corresponding outer selector. This happens instead of the normal nesting behavior.

.alert {
  // The parent selector can be used to add pseudo-classes to the outer
  // selector.
  &:hover {
    font-weight: bold;
  }

  // It can also be used to style the outer selector in a certain context, such
  // as a body set to use a right-to-left language.
  [dir=rtl] & {
    margin-left: 0;
    margin-right: 10px;
  }

  // You can even use it as an argument to pseudo-class selectors.
  :not(&) {
    opacity: 0.8;
  }
}
.alert
  // The parent selector can be used to add pseudo-classes to the outer
  // selector.
  &:hover
    font-weight: bold


  // It can also be used to style the outer selector in a certain context, such
  // as a body set to use a right-to-left language.
  [dir=rtl] &
    margin-left: 0
    margin-right: 10px


  // You can even use it as an argument to pseudo-class selectors.
  :not(&)
    opacity: 0.8
.alert:hover {
  font-weight: bold;
}
[dir=rtl] .alert {
  margin-left: 0;
  margin-right: 10px;
}
:not(.alert) {
  opacity: 0.8;
}

⚠️ Heads up!

Because the parent selector could be replaced by a type selector like h1, it’s only allowed at the beginning of compound selectors where a type selector would also be allowed. For example, span& is not allowed.

We’re looking into loosening this restriction, though. If you’d like to help make that happen, check out this GitHub issue.

Adding Suffixes

You can also use the parent selector to add extra suffixes to the outer selector. This is particularly useful when using a methodology like BEM that uses highly structured class names. As long as the outer selector ends with an alphanumeric name (like class, ID, and element selectors), you can use the parent selector to append additional text.

.accordion {
  max-width: 600px;
  margin: 4rem auto;
  width: 90%;
  font-family: "Raleway", sans-serif;
  background: #f4f4f4;

  &__copy {
    display: none;
    padding: 1rem 1.5rem 2rem 1.5rem;
    color: gray;
    line-height: 1.6;
    font-size: 14px;
    font-weight: 500;

    &--open {
      display: block;
    }
  }
}
.accordion
  max-width: 600px
  margin: 4rem auto
  width: 90%
  font-family: "Raleway", sans-serif
  background: #f4f4f4

  &__copy
    display: none
    padding: 1rem 1.5rem 2rem 1.5rem
    color: gray
    line-height: 1.6
    font-size: 14px
    font-weight: 500

    &--open
      display: block
.accordion {
  max-width: 600px;
  margin: 4rem auto;
  width: 90%;
  font-family: "Raleway", sans-serif;
  background: #f4f4f4;
}
.accordion__copy {
  display: none;
  padding: 1rem 1.5rem 2rem 1.5rem;
  color: gray;
  line-height: 1.6;
  font-size: 14px;
  font-weight: 500;
}
.accordion__copy--open {
  display: block;
}

In SassScript

The parent selector can also be used within SassScript. It’s a special expression that returns the current parent selector in the same format used by selector functions: a comma-separated list (the selector list) that contains space-separated lists (the complex selectors) that contain unquoted strings (the compound selectors).

.main aside:hover,
.sidebar p {
  parent-selector: &;
  // => ((unquote(".main") unquote("aside:hover")),
  //     (unquote(".sidebar") unquote("p")))
}
.main aside:hover,
.sidebar p
  parent-selector: &
  // => ((unquote(".main") unquote("aside:hover")),
  //     (unquote(".sidebar") unquote("p")))
.main aside:hover,
.sidebar p {
  parent-selector: .main aside:hover, .sidebar p;
}

If the & expression is used outside any style rules, it returns null. Since null is falsey, this means you can easily use it to determine whether a mixin is being called in a style rule or not.

@mixin app-background($color) {
  #{if(&, '&.app-background', '.app-background')} {
    background-color: $color;
    color: rgba(#fff, 0.75);
  }
}

@include app-background(#036);

.sidebar {
  @include app-background(#c6538c);
}
@mixin app-background($color)
  #{if(&, '&.app-background', '.app-background')}
    background-color: $color
    color: rgba(#fff, 0.75)



@include app-background(#036)

.sidebar
  @include app-background(#c6538c)
.app-background {
  background-color: #036;
  color: rgba(255, 255, 255, 0.75);
}

.sidebar.app-background {
  background-color: #c6538c;
  color: rgba(255, 255, 255, 0.75);
}

Advanced Nesting

You can use & as a normal SassScript expression, which means you can pass it to functions or include it in interpolation—even in other selectors! Using it in combination with selector functions and the @at-root rule allows you to nest selectors in very powerful ways.

For example, suppose you want to write a selector that matches the outer selector and an element selector. You could write a mixin like this one that uses the selector.unify() function to combine & with a user’s selector.

@use "sass:selector";

@mixin unify-parent($child) {
  @at-root #{selector.unify(&, $child)} {
    @content;
  }
}

.wrapper .field {
  @include unify-parent("input") {
    /* ... */
  }
  @include unify-parent("select") {
    /* ... */
  }
}
@use "sass:selector"

@mixin unify-parent($child)
  @at-root #{selector.unify(&, $child)}
    @content



.wrapper .field
  @include unify-parent("input")
    /* ... */

  @include unify-parent("select")
    /* ... */
.wrapper input.field {
  /* ... */
}

.wrapper select.field {
  /* ... */
}

⚠️ Heads up!

When Sass is nesting selectors, it doesn’t know what interpolation was used to generate them. This means it will automatically add the outer selector to the inner selector even if you used & as a SassScript expression. That’s why you need to explicitly use the @at-root rule to tell Sass not to include the outer selector.

© 2006–2022 the Sass team, and numerous contributors
Licensed under the MIT License.
https://sass-lang.com/documentation/style-rules/parent-selector