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Ring Width

Utilities for creating outline rings with box-shadows.

Default class reference

Class
Properties
ring-0box-shadow: var(--tw-ring-inset) 0 0 0 calc(0px + var(--tw-ring-offset-width)) var(--tw-ring-color);
ring-1box-shadow: var(--tw-ring-inset) 0 0 0 calc(1px + var(--tw-ring-offset-width)) var(--tw-ring-color);
ring-2box-shadow: var(--tw-ring-inset) 0 0 0 calc(2px + var(--tw-ring-offset-width)) var(--tw-ring-color);
ringbox-shadow: var(--tw-ring-inset) 0 0 0 calc(3px + var(--tw-ring-offset-width)) var(--tw-ring-color);
ring-4box-shadow: var(--tw-ring-inset) 0 0 0 calc(4px + var(--tw-ring-offset-width)) var(--tw-ring-color);
ring-8box-shadow: var(--tw-ring-inset) 0 0 0 calc(8px + var(--tw-ring-offset-width)) var(--tw-ring-color);
ring-inset--tw-ring-inset: inset;

Usage

Use the ring-{width} utilities to apply solid box-shadow of a specific thickness to an element. Rings are a semi-transparent blue color by default, similar to the default focus ring style in many systems.

<button class="... ring-0">ring-0</button>
<button class="... ring-2">ring-2</button>
<button class="... ring">ring</button>
<button class="... ring-4">ring-4</button>

Ring utilities compose gracefully with regular shadow-{size} utilities and can be combined on the same element.

You can also control the color, opacity, and offset of rings using the ringColor, ringOpacity, and ringOffsetWidth utilities.

Focus rings

The focus variant is enabled for ring-{width} utilities by default, which makes it easy to use them for custom focus styles by adding focus: to the beginning of any ring-{width} utility.

<button class="... focus:outline-none focus:ring-4 focus:ring-green-500 focus:ring-opacity-50">
  Button
</button>

The focus variant is enabled by default for the ringColor, ringOpacity, ringOffsetWidth, and ringOffsetColor utilities as well.

Inset rings

Use the ring-inset utility to force a ring to render on the inside of an element instead of the outside. This can be useful for elements at the edge of the screen where part of the ring wouldn’t be visible.

<button class="... ring-4 ring-pink-300">
  Default
</button>

<button class="... ring-4 ring-pink-300 ring-inset">
  Inset
</button>

Responsive

To control the ring width at a specific breakpoint, add a {screen}: prefix to any existing ring width utility. For example, use md:ring-4 to apply the ring-4 utility at only medium screen sizes and above.

<button class="ring-2 md:ring-4">
  <!-- ... -->
</button>

For more information about Tailwind’s responsive design features, check out the Responsive Design documentation.


Customizing

To customize which ring width utilities are generated, add your custom values under ringWidth key in the theme section of your tailwind.config.js file. You can use the DEFAULT key to specify which width is used for the plain ring utility.

// tailwind.config.js
module.exports = {
  theme: {
    extend: {
      ringWidth: {
        'DEFAULT': '2px',
        '6': '6px',
        '10': '10px',
      }
    }
  }
}

Learn more about customizing the default theme in the theme customization documentation.

Variants

By default, only responsive, focus-within and focus variants are generated for ring width utilities.

You can control which variants are generated for the ring width utilities by modifying the ringWidth property in the variants section of your tailwind.config.js file.

For example, this config will also generate hover and active variants:

  // tailwind.config.js
  module.exports = {
    variants: {
      extend: {
        // ...
+       ringWidth: ['hover', 'active'],
      }
    }
  }

Disabling

If you don't plan to use the ring width utilities in your project, you can disable them entirely by setting the ringWidth property to false in the corePlugins section of your config file:

  // tailwind.config.js
  module.exports = {
    corePlugins: {
      // ...
+     ringWidth: false,
    }
  }