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Border Opacity

Utilities for controlling the opacity of an element's border color.

Default class reference

Class
Properties
border-opacity-0--tw-border-opacity: 0;
border-opacity-5--tw-border-opacity: 0.05;
border-opacity-10--tw-border-opacity: 0.1;
border-opacity-20--tw-border-opacity: 0.2;
border-opacity-25--tw-border-opacity: 0.25;
border-opacity-30--tw-border-opacity: 0.3;
border-opacity-40--tw-border-opacity: 0.4;
border-opacity-50--tw-border-opacity: 0.5;
border-opacity-60--tw-border-opacity: 0.6;
border-opacity-70--tw-border-opacity: 0.7;
border-opacity-75--tw-border-opacity: 0.75;
border-opacity-80--tw-border-opacity: 0.8;
border-opacity-90--tw-border-opacity: 0.9;
border-opacity-95--tw-border-opacity: 0.95;
border-opacity-100--tw-border-opacity: 1;

Usage

Control the opacity of an element’s border color using the border-opacity-{amount} utilities.

100%
75%
50%
25%
0%
<div class="border-4 border-light-blue-500 border-opacity-100 ..."></div>
<div class="border-4 border-light-blue-500 border-opacity-75 ..."></div>
<div class="border-4 border-light-blue-500 border-opacity-50 ..."></div>
<div class="border-4 border-light-blue-500 border-opacity-25 ..."></div>
<div class="border-4 border-light-blue-500 border-opacity-0 ..."></div>

Responsive

To control an element’s border color opacity at a specific breakpoint, add a {screen}: prefix to any existing border color opacity utility. For example, use md:border-opacity-50 to apply the border-opacity-50 utility at only medium screen sizes and above.

<div class="border-2 border-blue-500 border-opacity-75 md:border-opacity-50">
  <!-- ... -->
</div>

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

Customizing

To customize the opacity values for all opacity-related utilities at once, use the opacity section of your tailwind.config.js theme configuration:

  // tailwind.config.js
  module.exports = {
    theme: {
      extend: {
        opacity: {
+         '10': '0.1',
+         '20': '0.2',
+         '95': '0.95',
        }
      }
    }
  }

If you want to customize only the border opacity utilities, use the borderOpacity section:

  // tailwind.config.js
  module.exports = {
    theme: {
      extend: {
        borderOpacity: {
+         '10': '0.1',
+         '20': '0.2',
+         '95': '0.95',
        }
      }
    }
  }

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

Variants

By default, only responsive, dark mode (if enabled), group-hover, focus-within, hover and focus variants are generated for border opacity utilities.

You can control which variants are generated for the border opacity utilities by modifying the borderOpacity property in the variants section of your tailwind.config.js file.

For example, this config will also generate active variants:

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

Disabling

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

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