Borders

Use border utilities to quickly style the border and border-radius of an element. Great for images, buttons, or any other element.

On this page

Border

Use border utilities to add or remove an element’s borders. Choose from all borders or one at a time.

Additive

<span class="border"></span>
<span class="border-top"></span>
<span class="border-end"></span>
<span class="border-bottom"></span>
<span class="border-start"></span>

Subtractive

<span class="border-0"></span>
<span class="border-top-0"></span>
<span class="border-end-0"></span>
<span class="border-bottom-0"></span>
<span class="border-start-0"></span>

Border color

Change the border color using utilities built on our theme colors.

<span class="border border-primary"></span>
<span class="border border-secondary"></span>
<span class="border border-success"></span>
<span class="border border-danger"></span>
<span class="border border-warning"></span>
<span class="border border-info"></span>
<span class="border border-light"></span>
<span class="border border-dark"></span>
<span class="border border-white"></span>

Border-width

<span class="border border-1"></span>
<span class="border border-2"></span>
<span class="border border-3"></span>
<span class="border border-4"></span>
<span class="border border-5"></span>

Border-radius

Add classes to an element to easily round its corners.

Example rounded image75x75 Example top rounded image75x75 Example right rounded image75x75 Example bottom rounded image75x75 Example left rounded image75x75 Completely round image75x75 Rounded pill image150x75 
<img src="..." class="rounded" alt="...">
<img src="..." class="rounded-top" alt="...">
<img src="..." class="rounded-end" alt="...">
<img src="..." class="rounded-bottom" alt="...">
<img src="..." class="rounded-start" alt="...">
<img src="..." class="rounded-circle" alt="...">
<img src="..." class="rounded-pill" alt="...">

Sizes

Use the scaling classes for larger or smaller rounded corners. Sizes range from 0 to 3, and can be configured by modifying the utilities API.

Example non-rounded image75x75 Example small rounded image75x75 Example default rounded image75x75 Example large rounded image75x75 
<img src="..." class="rounded-0" alt="...">
<img src="..." class="rounded-1" alt="...">
<img src="..." class="rounded-2" alt="...">
<img src="..." class="rounded-3" alt="...">

Sass

Variables

$border-width:                1px;
$border-widths: (
  1: 1px,
  2: 2px,
  3: 3px,
  4: 4px,
  5: 5px
);

$border-color:                $gray-300;

$border-radius:               .25rem;
$border-radius-sm:            .2rem;
$border-radius-lg:            .3rem;
$border-radius-pill:          50rem;

Mixins

@mixin border-radius($radius: $border-radius, $fallback-border-radius: false) {
  @if $enable-rounded {
    border-radius: valid-radius($radius);
  }
  @else if $fallback-border-radius != false {
    border-radius: $fallback-border-radius;
  }
}

@mixin border-top-radius($radius: $border-radius) {
  @if $enable-rounded {
    border-top-left-radius: valid-radius($radius);
    border-top-right-radius: valid-radius($radius);
  }
}

@mixin border-end-radius($radius: $border-radius) {
  @if $enable-rounded {
    border-top-right-radius: valid-radius($radius);
    border-bottom-right-radius: valid-radius($radius);
  }
}

@mixin border-bottom-radius($radius: $border-radius) {
  @if $enable-rounded {
    border-bottom-right-radius: valid-radius($radius);
    border-bottom-left-radius: valid-radius($radius);
  }
}

@mixin border-start-radius($radius: $border-radius) {
  @if $enable-rounded {
    border-top-left-radius: valid-radius($radius);
    border-bottom-left-radius: valid-radius($radius);
  }
}

@mixin border-top-start-radius($radius: $border-radius) {
  @if $enable-rounded {
    border-top-left-radius: valid-radius($radius);
  }
}

@mixin border-top-end-radius($radius: $border-radius) {
  @if $enable-rounded {
    border-top-right-radius: valid-radius($radius);
  }
}

@mixin border-bottom-end-radius($radius: $border-radius) {
  @if $enable-rounded {
    border-bottom-right-radius: valid-radius($radius);
  }
}

@mixin border-bottom-start-radius($radius: $border-radius) {
  @if $enable-rounded {
    border-bottom-left-radius: valid-radius($radius);
  }
}

Utilities API

Border utilities are declared in our utilities API in scss/_utilities.scss. Learn how to use the utilities API.

    "border": (
      property: border,
      values: (
        null: $border-width solid $border-color,
        0: 0,
      )
    ),
    "border-top": (
      property: border-top,
      values: (
        null: $border-width solid $border-color,
        0: 0,
      )
    ),
    "border-end": (
      property: border-right,
      class: border-end,
      values: (
        null: $border-width solid $border-color,
        0: 0,
      )
    ),
    "border-bottom": (
      property: border-bottom,
      values: (
        null: $border-width solid $border-color,
        0: 0,
      )
    ),
    "border-start": (
      property: border-left,
      class: border-start,
      values: (
        null: $border-width solid $border-color,
        0: 0,
      )
    ),
    "border-color": (
      property: border-color,
      class: border,
      values: map-merge($theme-colors, ("white": $white))
    ),
    "border-width": (
      property: border-width,
      class: border,
      values: $border-widths
    ),
    
    "rounded": (
      property: border-radius,
      class: rounded,
      values: (
        null: $border-radius,
        0: 0,
        1: $border-radius-sm,
        2: $border-radius,
        3: $border-radius-lg,
        circle: 50%,
        pill: $border-radius-pill
      )
    ),
    "rounded-top": (
      property: border-top-left-radius border-top-right-radius,
      class: rounded-top,
      values: (null: $border-radius)
    ),
    "rounded-end": (
      property: border-top-right-radius border-bottom-right-radius,
      class: rounded-end,
      values: (null: $border-radius)
    ),
    "rounded-bottom": (
      property: border-bottom-right-radius border-bottom-left-radius,
      class: rounded-bottom,
      values: (null: $border-radius)
    ),
    "rounded-start": (
      property: border-bottom-left-radius border-top-left-radius,
      class: rounded-start,
      values: (null: $border-radius)
    ),
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