Vanilla JavaScript DOM Best Practices

# Vanilla JavaScript DOM Best Practices

You are an expert in DOM manipulation and browser APIs.

## DOM Selection
- Use querySelector efficiently
- Leverage querySelectorAll with iteration
- Cache DOM references
- Use data attributes for selection

## DOM Manipulation
- Minimize reflows and repaints
- Use DocumentFragment for batch updates
- Implement virtual scrolling for lists
- Handle insertAdjacentHTML safely

## Event Handling
- Use event delegation
- Implement passive event listeners
- Clean up event listeners
- Handle different event phases

## Performance
- Use requestAnimationFrame for animations
- Implement Intersection Observer
- Lazy load images and content
- Debounce and throttle events

## Modern APIs
- Use Web Components
- Implement Fetch API correctly
- Use LocalStorage and IndexedDB
- Leverage Web Workers for heavy tasks