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Placeholder Opacity

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

Default class reference

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

Usage

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

<input class="placeholder-gray-500 placeholder-opacity-100 ..." placeholder="jane@example.com">
<input class="placeholder-gray-500 placeholder-opacity-75 ..." placeholder="jane@example.com">
<input class="placeholder-gray-500 placeholder-opacity-50 ..." placeholder="jane@example.com">
<input class="placeholder-gray-500 placeholder-opacity-25 ..." placeholder="jane@example.com">
<input class="placeholder-gray-500 placeholder-opacity-0 ..." placeholder="jane@example.com">

Responsive

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

<input class="placeholder-gray-500 placeholder-opacity-75 md:placeholder-opacity-50 ..." placeholder="jane@example.com">

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: {
+         '15': '0.15',
+         '35': '0.35',
+         '65': '0.65',
        }
      }
    }
  }

If you want to customize only the placeholder opacity utilities, use the placeholderOpacity section:

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

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

Variants

默認情況下, 只有 響應式、深色模式 (如果啟用) 和 focus 的 placeholder opacity 變化模式 (variants) 會產生。

tailwind.config.jsvariants 區塊中變更 placeholderOpacity 屬性來決定有哪些變化模式會生成。

舉個例子來說,這個設定將會生成 響應式 和 hover 的變化模式。

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

Disabling

如果你不打算在專案中使用 placeholder opacity 功能,可以在你的設定檔裡的 corePlugins 屬性中將 placeholderOpacity 設定為 false 來停用功能:

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