css-inspector

A skill for explaining which CSS rules win when several rules affect the same web element. It examines rule priority, ordering, inheritance, and selectors, which are patterns that identify elements such as classes or tags.

In plain words
What is it for?
Use it to debug conflicting styles, inspect specificity and cascade order, trace inherited values, and simplify complicated CSS.
Why use it?
It helps find why a style is overridden, inherited unexpectedly, or harder to change than expected.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/andronics/claude-plugin-css-pro/css-inspector
Any agent
npx skills add andronics/claude-plugin-css-pro --skill css-inspector
Clone the repo
git clone --depth 1 https://github.com/andronics/claude-plugin-css-pro

Made for: Claude Code, Codex.

Per session 41 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,180 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00041 $0.03180
Opus 5 $0.00020 $0.01590
Sonnet 5 $0.00008 $0.00636
Haiku 4.5 $0.00004 $0.00318

Measured yesterday against content hash f20a61c0c0c5, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

css-inspector scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/css-inspector/SKILL.md · 603 lines

How it starts

The opening of the file, as written. The whole thing — 603 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CSS Inspector Skill

This skill helps you understand how CSS rules interact through the cascade, specificity, and inheritance. I'll analyze your CSS to reveal computed styles, explain why certain rules apply, and suggest simplifications.

What I Can Analyze

Specificity Calculations

  • Calculate selector specificity
  • Compare competing rules
  • Identify specificity issues
  • Suggest lower-specificity alternatives

Cascade Analysis

  • Show rule application order
  • Identify overridden rules
  • Explain cascade layers
  • Track source order impact

Inheritance Tracking

  • Show inherited properties
  • Identify inheritance chains
  • Explain computed values
  • Detect inheritance issues

Selector Complexity

  • Measure selector depth
  • Identify overly specific selectors
  • Find redundant selectors
  • Suggest simplifications

Specificity Explained

Specificity Formula: (a, b, c, d)

  • a: Inline styles (1,0,0,0)
  • b: ID selectors (#id)
  • c: Class selectors (.class), attribute selectors ([attr]), pseudo-classes (:hover)
  • d: Element selectors (div), pseudo-elements (::before)

Examples

/* (0,0,0,1) */
div { }

/* (0,0,1,0) */
.button { }

/* (0,0,1,1) */
div.button { }

/* (0,0,2,0) */
.button.primary { }

/* (0,0,2,1) */
nav.button.primary { }

/* (0,1,0,0) */
#header { }

/* (0,1,1,1) */
#header .button { }

/* (0,0,3,0) */
.nav .item .link { }

/* (1,0,0,0) */
<div style="color: red"> /* Inline style */

Specificity Comparison

/* Which rule wins? */

/* (0,0,1,0) - .button */
.button {
  color: blue;
}

/* (0,0,2,0) - .nav .button - WINS */
.nav .button {
  color: red;
}

/* (0,1,0,0) - #header - WINS */
#header {
  color: green;
}

/* !important overrides specificity */
.button {
  color: yellow !important; /* WINS over everything except inline !important */
}

Cascade Order

Rule Resolution Order (Highest to Lowest)

  1. Inline styles with !important
    <div style="color: red !important">
    

Read the full file on GitHub · 603 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 603 lines · 41 tokens per session scan A f20a61c0c0c5

Subscribe to this mod's changes

css-inspector is a skill published in the GitHub repository andronics/claude-plugin-css-pro (2 stars, last pushed 10mo ago), licensed MIT. It adds 41 tokens to every session and 3,180 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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