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css-math-units

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Explain, derive, and debug CSS math for measurement units, calc(), min(), max(), clamp(), custom properties, inheritance, em/rem scaling, percentages, viewport units, and box model formulas. Use when CSS dimensions compute unexpectedly, when mixing units, when building scalable spacing/type systems, or when reviewing box sizing and inherited values.

QUICK START

How to use this skill

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  2. Copy the prompt below and paste it into your agent.
  3. Review the proposed files and risks before you approve installation.
Prompt to paste
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Source SKILL.md: https://github.com/hashgraph-online/awesome-codex-plugins/blob/HEAD/plugins/LVTD-LLC/skills/skills/css-math-units/SKILL.md

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Copying this prompt does not install or run the skill. Review third-party files before use. Codex skill guide

CSS Math Units

Use this skill to trace how CSS values become computed layout values. It is useful for unit conversion, inherited size multiplication, calc expressions, custom property math, and box model sizing.

Quick Start

  1. Read guidelines.md to select the smallest relevant file set.
  2. Load references/css-calculations/rules.md for implementation decisions.
  3. Load references/css-calculations/examples.md when editing code.
  4. Use workflows/debug-css-calculation.md for multi-step derivation or debugging.

Contents

ResourcePurpose
guidelines.mdRoutes tasks to the right reference files
references/source-map.mdBook source and chapter/section traceability
references/css-calculations/knowledge.mdCore concepts and terminology
references/css-calculations/rules.mdPractical rules, guidelines, and exceptions
references/css-calculations/examples.mdBad/good examples and refactoring approach
references/css-calculations/patterns.mdReusable formula and implementation patterns
references/css-calculations/checklist.mdReview checklist and red flags
workflows/debug-css-calculation.mdStep-by-step workflow

Source

Derived from Math for Web Design by Paul McFedries, Chapter 3: Math basics for CSS. Citations are tracked in references/source-map.md.