tomevault-io Color Tools Skill
This skill helps you create accessible, harmonious color palettes and ensures your colors meet WCAG contrast requirements. I provide color calculations, palette generation, and accessibility validation.
What I Can Do
Color Contrast Checking
- Calculate contrast ratios
- Verify WCAG AA/AAA compliance
- Suggest accessible alternatives
- Check text/background combinations
Palette Generation
- Create tint/shade scales (50-900)
- Generate color harmonies
- Build complementary palettes
- Design theme variations
Color Conversions
- HEX ↔ RGB ↔ HSL
- Calculate opacity variations
- Generate CSS custom properties
- Create color tokens
Accessibility Tools
- Find accessible color pairs
- Suggest minimum contrast fixes
- Validate interactive state colors
- Check large text requirements
WCAG Contrast Requirements
Minimum Ratios
- Normal text: 4.5:1 (AA), 7:1 (AAA)
- Large text (18px+ or 14px+ bold): 3:1 (AA), 4.5:1 (AAA)
- UI components: 3:1 (AA)
- Graphical objects: 3:1 (AA)
Contrast Formula
Contrast Ratio = (L1 + 0.05) / (L2 + 0.05) Where L1 is lighter color luminance and L2 is darker
Example: Contrast Checking
You: "Check if #3b82f6 on white background is accessible"
I'll provide:
Color: #3b82f6 (Blue)
Background: #ffffff (White)
Contrast Ratio: 4.52:1
WCAG Compliance:
✓ Normal text AA (4.5:1 required) - PASS
✗ Normal text AAA (7:1 required) - FAIL
✓ Large text AA (3:1 required) - PASS
✓ Large text AAA (4.5:1 required) - PASS
✓ UI Components (3:1 required) - PASS
Recommendation:
For AAA compliance with normal text, use #2563eb (darker blue)
New contrast: 7.02:1 - Passes all requirements
Palette Generation
Tint & Shade Scale
/* Generate 50-900 scale from base color */
:root {
/* Base color: #3b82f6 */
--color-blue-50: #eff6ff; /* 90% lighter */
--color-blue-100: #dbeafe; /* 80% lighter */
--color-blue-200: #bfdbfe; /* 60% lighter */
--color-blue-300: #93c5fd; /* 40% lighter */
--color-blue-400: #60a5fa; /* 20% lighter */
--color-blue-500: #3b82f6; /* Base */
--color-blue-600: #2563eb; /* 20% darker */
--color-blue-700: #1d4ed8; /* 40% darker */
--color-blue-800: #1e40af; /* 60% darker */
--color-blue-900: #1e3a8a; /* 80% darker */
}
/* Usage guide:
* 50-100: Backgrounds, subtle highlights
* 200-300: Hover states, borders
* 400-600: Primary UI, text on light backgrounds
* 700-900: Text, emphasis, dark themes
*/
Color Harmonies
Complementary Colors
/* Base: #3b82f6 (Blue) */
:root {
--color-primary: #3b82f6; /* Blue (210°) */
--color-complement: #f6823b; /* Orange (30°) - opposite */
}
Analogous Colors
/* Base: #3b82f6 (Blue) */
:root {
--color-primary: #3b82f6; /* Blue (210°) */
--color-analogous-1: #3bf6db; /* Cyan (180°) */
--color-analogous-2: #823bf6; /* Purple (270°) */
}
Triadic Colors
/* Base: #3b82f6 (Blue) */
:root {
--color-primary: #3b82f6; /* Blue (210°) */
--color-triadic-1: #f6db3b; /* Yellow (90°) */
--color-triadic-2: #db3bf6; /* Magenta (330°) */
}
Split-Complementary
/* Base: #3b82f6 (Blue) */
:root {
--color-primary: #3b82f6; /* Blue (210°) */
--color-split-1: #f6db3b; /* Yellow-Orange (45°) */
--color-split-2: #f6493b; /* Red-Orange (15°) */
}
Accessible Color Palettes
Light Theme
:root {
/* Backgrounds - Lightest colors */
--color-bg: #ffffff; /* Pure white */
--color-bg-secondary: #f9fafb; /* Near white */
--color-bg-tertiary: #f3f4f6; /* Light gray */
/* Text - Darkest colors (AAA contrast) */
--color-text-primary: #111827; /* 16.04:1 */
--color-text-secondary: #4b5563; /* 8.49:1 */
--color-text-tertiary: #6b7280; /* 5.77:1 */
/* Primary color (accessible) */
--color-primary: #2563eb; /* 7.02:1 on white */
--color-primary-hover: #1d4ed8; /* 9.52:1 on white */
/* Interactive states */
--color-link: #2563eb; /* 7.02:1 */
--color-link-hover: #1d4ed8; /* 9.52:1 */
--color-link-visited: #7c3aed; /* 7.09:1 */
/* Status colors (all AAA compliant) */
--color-success: #047857; /* 7.36:1 */
--color-warning: #b45309; /* 7.01:1 */
--color-error: #dc2626; /* 7.29:1 */
}
Dark Theme
[data-theme="dark"] {
/* Backgrounds - Darkest colors */
--color-bg: #111827; /* Very dark gray */
--color-bg-secondary: #1f2937; /* Dark gray */
--color-bg-tertiary: #374151; /* Medium-dark gray */
/* Text - Lightest colors (AAA contrast) */
--color-text-primary: #f9fafb; /* 14.73:1 */
--color-text-secondary: #d1d5db; /* 10.31:1 */
--color-text-tertiary: #9ca3af; /* 6.16:1 */
/* Primary color (lighter for dark mode) */
--color-primary: #60a5fa; /* 7.38:1 on dark bg */
--color-primary-hover: #93c5fd; /* 10.73:1 on dark bg */
/* Status colors (adjusted for dark mode) */
--color-success: #34d399; /* 7.53:1 */
--color-warning: #fbbf24; /* 13.44:1 */
--color-error: #f87171; /* 7.03:1 */
}
Color Conversion Examples
HEX to RGB
#3b82f6 → rgb(59, 130, 246)
Calculation:
R: 3b (hex) = 59 (decimal)
G: 82 (hex) = 130 (decimal)
B: f6 (hex) = 246 (decimal)
RGB to HSL
rgb(59, 130, 246) → hsl(217, 91%, 60%)
Calculation:
H: 217° (hue)
S: 91% (saturation)
L: 60% (lightness)
Adding Opacity
/* HEX with alpha */
--color-primary: #3b82f6;
--color-primary-10: #3b82f61a; /* 10% opacity */
--color-primary-50: #3b82f680; /* 50% opacity */
/* RGB with alpha */
--color-primary-rgb: 59, 130, 246;
--color-primary-10: rgba(var(--color-primary-rgb), 0.1);
--color-primary-50: rgba(var(--color-primary-rgb), 0.5);
/* HSL with alpha */
--color-primary: hsl(217, 91%, 60%);
--color-primary-10: hsl(217, 91%, 60%, 0.1);
--color-primary-50: hsl(217, 91%, 60%, 0.5);
Color Token System
Complete Token Architecture
:root {
/* 1. Global tokens - Raw colors */
--color-blue-500: #3b82f6;
--color-blue-600: #2563eb;
--color-gray-50: #f9fafb;
--color-gray-900: #111827;
/* 2. Semantic tokens - Purpose */
--color-primary: var(--color-blue-600);
--color-text-primary: var(--color-gray-900);
--color-surface: var(--color-gray-50);
/* 3. Component tokens - Specific */
--button-bg-primary: var(--color-primary);
--button-text-primary: white;
--card-bg: var(--color-surface);
}
Checking Interactive States
Button States Example
.button-primary {
/* Default state */
background: #2563eb; /* 7.02:1 on white */
color: white;
/* Hover state */
&:hover {
background: #1d4ed8; /* 9.52:1 on white */
}
/* Focus state */
&:focus-visible {
outline: 2px solid #2563eb;
outline-offset: 2px;
/* Outline must have 3:1 contrast with adjacent colors */
}
/* Active/pressed state */
&:active {
background: #1e40af; /* 11.19:1 on white */
}
/* Disabled state */
&:disabled {
background: #93c5fd; /* 3.24:1 - may fail for text */
color: #6b7280; /* Reduced contrast acceptable when disabled */
opacity: 0.6;
}
}
Color Accessibility Tips
✓ Good Practices
- Test all text/background combinations
- Check hover and focus states
- Verify status colors (success, warning, error)
- Don't rely on color alone (use icons/text too)
- Test with color blindness simulators
- Provide high contrast mode
- Use semantic color names
❌ Common Mistakes
- Light gray text on white (#999 on #fff = 2.85:1 - fails)
- Relying only on color for information
- Insufficient contrast in disabled states
- Forgetting to test dark mode
- Not checking focus indicators
- Ignoring links and interactive elements
Example Usage
You: "Create an accessible blue palette for a light theme"
I'll provide:
:root {
/* Blue palette - All colors tested for accessibility */
/* Primary actions - AAA compliant on white */
--color-primary: #1d4ed8; /* 9.52:1 */
--color-primary-hover: #1e40af; /* 11.19:1 */
/* Backgrounds */
--color-primary-bg: #eff6ff; /* Subtle background */
--color-primary-border: #93c5fd; /* 3.24:1 - good for borders */
/* Text on primary buttons */
--color-primary-text: #ffffff; /* 9.52:1 on #1d4ed8 */
/* Links */
--color-link: #2563eb; /* 7.02:1 - AAA for large text */
--color-link-hover: #1d4ed8; /* 9.52:1 - AAA */
--color-link-visited: #7c3aed; /* 7.09:1 - AAA */
/* Status indicators */
--color-info: #0284c7; /* 7.24:1 */
--color-info-bg: #e0f2fe; /* Background for info messages */
}
/* Usage example */
.button-primary {
background: var(--color-primary);
color: var(--color-primary-text);
}
.button-primary:hover {
background: var(--color-primary-hover);
}
.link {
color: var(--color-link);
}
.link:hover {
color: var(--color-link-hover);
}
Just Ask!
Tell me what you need:
- "Check contrast for #3b82f6 on white"
- "Generate a blue color palette"
- "Create accessible dark theme colors"
- "Find a complementary color for #2563eb"
- "Make this color more accessible"
- "Convert #3b82f6 to RGB and HSL"
I'll help you create accessible, beautiful color systems!
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