Semantic Theming

Semantic Theming Skill

Use semantic design tokens instead of raw colors. This skill teaches Claude to write theme-compliant code from the start.

Detection Criteria

This skill applies when the project has ANY of:

• docs/THEMING.md exists
• eslint-rules/no-raw-colors.js exists
• ESLint config includes wescobar/no-raw-colors or similar theming rule
• src/index.css defines CSS custom properties (e.g., --color-primary)

Quick check: Look for these indicators before applying this skill.

When to Use

• Writing or editing React components with className
• Using Tailwind utility classes for colors/backgrounds/borders
• Working with cn(), clsx(), or cva() class composition
• Styling any UI element with colors

Forbidden Patterns

Raw Color Literals

// FORBIDDEN - Will fail ESLint
style={{ color: '#ff0000' }}
style={{ backgroundColor: 'rgb(255, 0, 0)' }}
style={{ borderColor: 'hsl(0, 100%, 50%)' }}

Non-Semantic Tailwind Classes

// FORBIDDEN - Will fail ESLint
className="bg-red-500"
className="text-white"
className="border-blue-300"
className="bg-slate-900 text-gray-100"
className="from-purple-500 via-pink-500 to-red-500"

Correct Patterns

Semantic Token Classes

// CORRECT - Use semantic tokens
className="bg-surface text-primary"
className="bg-surface-secondary border-primary"
className="bg-error text-error"
className="bg-success text-success"
className="text-secondary bg-primary"

Common Semantic Tokens

With Class Composition

// CORRECT - Semantic tokens in cn/clsx/cva
import { cn } from '@/lib/utils';

className={cn(
  "bg-surface text-primary",
  isActive && "bg-primary text-surface",
  hasError && "border-error text-error"
)}

CVA Variants

// CORRECT - Semantic tokens in cva
const buttonVariants = cva(
  "bg-surface text-primary border-primary", // Base
  {
    variants: {
      variant: {
        primary: "bg-primary text-surface",
        error: "bg-error text-surface",
        success: "bg-success text-surface",
      }
    }
  }
);

Escape Hatches

When absolutely necessary (rare):

// Line-level disable
// eslint-disable-next-line wescobar/no-raw-colors
className="bg-red-500" // Legacy code migration

// File-level disable (very rare)
/* eslint-disable wescobar/no-raw-colors */

Use sparingly - prefer fixing to disabling.

Migration Examples

Project-Specific Tokens

Check docs/THEMING.md or src/index.css for the full list of available semantic tokens in this project. Token names may vary between projects.

Integration with ESLint

The no-raw-colors ESLint rule enforces this at:

• Pre-commit hooks (blocks commit)
• IDE integration (inline errors)
• CI/CD pipeline

Generate correct code from the start to avoid fix cycles.

Related Skills

• validate-lint - Run linting validation
• quality-gate - Complete quality checks including lint

Validation

After writing styled code:

1. Check for any raw colors or non-semantic Tailwind classes
2. Replace with semantic tokens from the project's theme
3. If unsure, check docs/THEMING.md for available tokens