Tailwind Markhamsquareventures

---
name: tailwind
description: How to work effectively with Tailwind CSS, always use when styling frontend features
---

# Tailwind

## Instructions

- Use Tailwind CSS classes to style HTML, check and use existing tailwind conventions within the project before writing your own.
- Offer to extract repeated patterns into components that match the project's conventions (i.e. Blade, JSX, Vue, etc..)
- Think through class placement, order, priority, and defaults - remove redundant classes, add classes to parent or child carefully to limit repetition, group elements logically
- Always use Tailwind CSS v4 - do not use the deprecated utilities.
- `corePlugins` is not supported in Tailwind v4.

### Dark Mode

- If existing pages and components support dark mode, new pages and components must support dark mode in a similar way, typically using `dark:`.

## Examples

- In Tailwind v4, configuration is CSS-first using the `@theme` directive — no separate `tailwind.config.js` file is needed.
  <code-snippet name="Extending Theme in CSS" lang="css">
  @theme {
  --color-brand: oklch(0.72 0.11 178);
  }
  </code-snippet>

- In Tailwind v4, you import Tailwind using a regular CSS `@import` statement, not using the `@tailwind` directives used in v3:

<code-snippet name="Tailwind v4 Import Tailwind Diff" lang="diff">
   - @tailwind base;
   - @tailwind components;
   - @tailwind utilities;
   + @import "tailwindcss";
</code-snippet>

### Replaced Utilities

- Tailwind v4 removed deprecated utilities. Do not use the deprecated option - use the replacement.
- Opacity values are still numeric.

| Deprecated | Replacement |
|------------+--------------|
| bg-opacity-_ | bg-black/_ |
| text-opacity-_ | text-black/_ |
| border-opacity-_ | border-black/_ |
| divide-opacity-_ | divide-black/_ |
| ring-opacity-_ | ring-black/_ |
| placeholder-opacity-_ | placeholder-black/_ |
| flex-shrink-_ | shrink-_ |
| flex-grow-_ | grow-_ |
| overflow-ellipsis | text-ellipsis |
| decoration-slice | box-decoration-slice |
| decoration-clone | box-decoration-clone |

### Spacing

- When listing items, use gap utilities for spacing, don't use margins.

<code-snippet name="Valid Flex Gap Spacing Example" lang="html">
    <div class="flex gap-8">
        <div>Superior</div>
        <div>Michigan</div>
        <div>Erie</div>
    </div>
</code-snippet>