create-nova-expo-template/template/.claude/skills/building-native-ui/references/gradients.md

A template for creating a new React Native app using Expo and TypeScript, with a focus on performance and best practices.

# CSS Gradients

> **New Architecture Only**: CSS gradients require React Native's New Architecture (Fabric). They are not available in the old architecture or Expo Go.

Use CSS gradients with the `experimental_backgroundImage` style property.

## Linear Gradients

```tsx
// Top to bottom
<View style={{
  experimental_backgroundImage: 'linear-gradient(to bottom, rgba(0, 0, 0, 0) 0%, rgba(0, 0, 0, 1) 100%)'
}} />

// Left to right
<View style={{
  experimental_backgroundImage: 'linear-gradient(to right, #ff0000 0%, #0000ff 100%)'
}} />

// Diagonal
<View style={{
  experimental_backgroundImage: 'linear-gradient(45deg, #ff0000 0%, #00ff00 50%, #0000ff 100%)'
}} />

// Using degrees
<View style={{
  experimental_backgroundImage: 'linear-gradient(135deg, transparent 0%, black 100%)'
}} />
```

## Radial Gradients

```tsx
// Circle at center
<View style={{
  experimental_backgroundImage: 'radial-gradient(circle at center, rgba(255, 0, 0, 1) 0%, rgba(0, 0, 255, 1) 100%)'
}} />

// Ellipse
<View style={{
  experimental_backgroundImage: 'radial-gradient(ellipse at center, #fff 0%, #000 100%)'
}} />

// Positioned
<View style={{
  experimental_backgroundImage: 'radial-gradient(circle at top left, #ff0000 0%, transparent 70%)'
}} />
```

## Multiple Gradients

Stack multiple gradients by comma-separating them:

```tsx
<View style={{
  experimental_backgroundImage: `
    linear-gradient(to bottom, transparent 0%, black 100%),
    radial-gradient(circle at top right, rgba(255, 0, 0, 0.5) 0%, transparent 50%)
  `
}} />
```

## Common Patterns

### Overlay on Image

```tsx
<View style={{ position: 'relative' }}>
  <Image source={{ uri: '...' }} style={{ width: '100%', height: 200 }} />
  <View style={{
    position: 'absolute',
    inset: 0,
    experimental_backgroundImage: 'linear-gradient(to top, rgba(0, 0, 0, 0.8) 0%, transparent 50%)'
  }} />
</View>
```

### Frosted Glass Effect

```tsx
<View style={{
  experimental_backgroundImage: 'linear-gradient(135deg, rgba(255, 255, 255, 0.1) 0%, rgba(255, 255, 255, 0.05) 100%)',
  backdropFilter: 'blur(10px)',
}} />
```

### Button Gradient

```tsx
<Pressable style={{
  experimental_backgroundImage: 'linear-gradient(to bottom, #4CAF50 0%, #388E3C 100%)',
  padding: 16,
  borderRadius: 8,
}}>
  <Text style={{ color: 'white', textAlign: 'center' }}>Submit</Text>
</Pressable>
```

## Important Notes

- Do NOT use `expo-linear-gradient` — use CSS gradients instead
- Gradients are strings, not objects
- Use `rgba()` for transparency, or `transparent` keyword
- Color stops use percentages (0%, 50%, 100%)
- Direction keywords: `to top`, `to bottom`, `to left`, `to right`, `to top left`, etc.
- Degree values: `45deg`, `90deg`, `135deg`, etc.