CSS Modern Features Agent Skill: Enforce Modern CSS Practices in AI Coding Agents
There's a new agent skill on GitHub called css-modern-features that enforces modern CSS practices based on your project's browser targets. It covers 57+ CSS features across color, layout, selectors, animation, typography, positioning, and component patterns.
How It Works
The skill hooks into AI coding agents and restricts CSS output to only modern, browser-target-appropriate features. For example, if your project targets modern browsers, it would prefer display: grid over float-based layouts, clamp() for fluid typography, and :has() for parent selection. You define the browser targets, and the skill adjusts which features are allowed.
Supported Agents
The skill works with:
- Claude Code
- Cursor
- Windsurf
- Codex
- Cline
- GitHub Copilot
Why This Matters
AI coding agents frequently generate outdated CSS (e.g., float, clearfix, vendor prefixes) because their training data includes old code. This skill forces them to stick to modern features, saving you from manual refactoring. It's particularly useful for teams maintaining codebases that must target specific browser versions (e.g., 'last 2 versions' via Browserslist).
Repo: github.com/rushenn/css-modern-features
The Reddit thread (linked below) has additional community discussion on customizing the feature set.
📖 Read the full source: r/ClaudeAI
👀 See Also
SkillOpt: Optimizing Markdown Skill Files as Trainable Parameters for AI Agents
SkillOpt formalizes the ad-hoc process of editing markdown skill files for AI coding agents, using frontier models to propose bounded edits gated against validation sets. Best skills converge with 1-4 accepted edits out of many proposals, and transfer across models like Codex to Claude Code.
Persistent Memory for Claude: Local Stack with MCP, 39ms Retrieval, 82% Token Reduction
A developer built a persistent memory layer for Claude using local vector search (Qdrant + Qwen3) and MCP integration, achieving 82% token reduction, 39ms hot-path retrieval, and session crystallization via L4 nodes.
Local AI Image Critic Tool Uses Ollama Vision Models for Feedback
A developer has created a free desktop application that analyzes AI-generated images locally using Ollama vision models. The tool provides structured feedback reports including improvement suggestions and prompt upgrades.
Skills Creator Tool for OpenClaw Helps Developers Package Workflows
A developer created a skill called skills-creator that guides users through creating quality skills for OpenClaw, addressing common pitfalls like vague descriptions and documentation-like instructions. It's available on ClawHub and provides a design-driven approach with description formulas, checklists, and complexity tiers.