visual-design-foundations

# Visual Design Foundations

Build cohesive, accessible visual systems using typography, color, spacing, and iconography fundamentals.

## When to Use This Skill

- Establishing design tokens for a new project
- Creating or refining a spacing and sizing system
- Selecting and pairing typefaces
- Building accessible color palettes
- Designing icon systems and visual assets
- Improving visual hierarchy and readability
- Auditing designs for visual consistency
- Implementing dark mode or theming

## Core Systems

### 1. Typography Scale

**Modular Scale** (ratio-based sizing):

```css
:root {
  --font-size-xs: 0.75rem; /* 12px */
  --font-size-sm: 0.875rem; /* 14px */
  --font-size-base: 1rem; /* 16px */
  --font-size-lg: 1.125rem; /* 18px */
  --font-size-xl: 1.25rem; /* 20px */
  --font-size-2xl: 1.5rem; /* 24px */
  --font-size-3xl: 1.875rem; /* 30px */
  --font-size-4xl: 2.25rem; /* 36px */
  --font-size-5xl: 3rem; /* 48px */
}
```

**Line Height Guidelines**:
| Text Type | Line Height |
|-----------|-------------|
| Headings | 1.1 - 1.3 |
| Body text | 1.5 - 1.7 |
| UI labels | 1.2 - 1.4 |

### 2. Spacing System

**8-point grid** (industry standard):

```css
:root {
  --space-1: 0.25rem; /* 4px */
  --space-2: 0.5rem; /* 8px */
  --space-3: 0.75rem; /* 12px */
  --space-4: 1rem; /* 16px */
  --space-5: 1.25rem; /* 20px */
  --space-6: 1.5rem; /* 24px */
  --space-8: 2rem; /* 32px */
  --space-10: 2.5rem; /* 40px */
  --space-12: 3rem; /* 48px */
  --space-16: 4rem; /* 64px */
}
```

### 3. Color System

**Semantic color tokens**:

```css
:root {
  /* Brand */
  --color-primary: #2563eb;
  --color-primary-hover: #1d4ed8;
  --color-primary-active: #1e40af;

  /* Semantic */
  --color-success: #16a34a;
  --color-warning: #ca8a04;
  --color-error: #dc2626;
  --color-info: #0891b2;

  /* Neutral */
  --color-gray-50: #f9fafb;
  --color-gray-100: #f3f4f6;
  --color-gray-200: #e5e7eb;
  --color-gray-300: #d1d5db;
  --color-gray-400: #9ca3af;
  --color-gray-500: #6b7280;