# Uncss

> Use this skill when the user wants to remove unused CSS from stylesheets by analyzing the actual HTML or templates used in their project.

- Skill: `javimosch/uncss` (Agent Skill)
- Install (CLI): `npx skillmds@latest add javimosch/uncss`
- Raw SKILL.md: https://api.skillmd.com/api/skills/javimosch/uncss/raw
- Safety review: PASS (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Web & Frontend
- Author: javimosch (https://skillmd.com/u/javimosch)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/javimosch/uncss

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# UnCSS Plugin

UnCSS removes unused CSS rules by scanning HTML/JS templates against stylesheets.

## Usage Examples

- "remove unused CSS from styles.css based on index.html"
- "purge unused CSS across multiple HTML pages"
- "generate a lean CSS file for production"
- "analyze CSS coverage across templates"

## Installation

```bash
npm install -g uncss
```

## Key Features
- Unused CSS rule removal
- HTML/JS template scanning
- Multiple page/file support
- PhantomJS and Puppeteer backends
- CSS file size reduction
- Production-ready lean CSS generation
- Media query preservation
- Ignored selector configuration