# Cssnano

> Use this skill when the user wants to optimize and minify CSS for production — reduce file size, merge rules, drop duplicates, and compress colors via PostCSS.

- Skill: `javimosch/cssnano` (Agent Skill)
- Install (CLI): `npx skillmds@latest add javimosch/cssnano`
- Raw SKILL.md: https://api.skillmd.com/api/skills/javimosch/cssnano/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/cssnano

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# cssnano Plugin

cssnano minifies and optimizes CSS using PostCSS plugins. Reduces file size by removing whitespace, merging rules, and normalizing values.

## Commands

- `cssnano _ _ <args>` — Passthrough

## Usage Examples

- "minify styles.css to styles.min.css"
- "optimize all CSS files in a directory"
- "preview optimization results without writing"
- "merge multiple CSS files and optimize"

## Installation

```bash
npm install -g cssnano
```

## Key Features
- Whitespace and comment removal
- Rule merging and consolidation
- Duplicate selector elimination
- Color compression and normalization
- Value optimization (z-index, calc, etc.)
- Font-face and keyframe deduplication
- PostCSS plugin ecosystem support
- Configurable optimization presets