Add Tailwind CSS language server to CSS language settings

[jsparkdev]

Although Zed offers native support for Tailwind CSS, users may encounter syntax warnings for custom at-rules and directives (e.g., @apply, @tailwind) if no language server is explicitly configured, as detailed in the official guide.

This pull request addresses this by adding the Tailwind CSS Language Server to the default configuration. This ensures a smooth, warning-free editing experience for Tailwind CSS stylesheets right out of the box, requiring zero configuration from the developer.

Before

After

Release Notes:

• N/A

[danilo-leal]

Hey, @jsparkdev thanks for the PR! I've been chatting with @thecrypticace from the Tailwind team and there's a possibility this could be fixed on the Tailwind LSP itself. Let's wait for an update from Jordan before moving forward with this (I do want to have it fixed, though. I've been seeing these same warnings for a while now, so thanks for jumping into it!).

[jsparkdev]

@danilo-leal

Got it. Thank you for letting me know!

[thecrypticace]

It's not that we'd "fix" it in the Tailwind CSS language server — Zed would still require changes but this one is not sufficient as it doesn't provide general CSS completions at all.

We've only recently published our fork of VSCode's CSS language server in our @tailwindcss/language-server package in v0.14.27 two days ago. This is what our VSCode extension has used for years. You can see the PR for that here.

I think the best course of action would be to match our VSCode extension behavior:

1. Add a second "Tailwind CSS" language that works just like "CSS".
2. It should use the normal tailwindcss-language-server binary from @tailwindcss/language-server.
3. It should also load the css-language-server binary from @tailwindcss/language-server instead of vscode-css-language-server (== using our fork instead of the default).

The LSP language ID of the new language is tailwindcss.

These could probably be integrated into the one language server binary but they've historically been separate and, for VSCode, the second one is booted on demand when you first open a CSS file in the "Tailwind CSS" language.

[thecrypticace]

To fix the warnings in the short term you can override the vscode-css-language-server to point at a different binary in your Zed settings (this is what I do currently):

"lsp": {
  "vscode-css-language-server": {
    "binary": {
      "path": "/Users/jordanpittman/Library/Caches/fnm_multishells/57219_1755626184882/bin/node",
      "arguments": [
        "/Users/jordanpittman/Library/Application Support/Zed/languages/tailwindcss-language-server/node_modules/.bin/css-language-server",
        "--stdio"
      ]
    }
  }
}

You'll want to update path to point to wherever you have Node.js installed and then the first argument path will be different based on your user name (on macOS at least). I'm not sure what the path is for users testing on Windows.

[jgabriel98]

hey guys! any progress on this?
@danilo-leal did the tailwind team gave an answer yet?

Just checking by, to better set my expectations
(tailwind not properly working is the only think holding me back from vscode to zed)