- Use a CSS-in-JS library (styled-components, Emotion, or Panda CSS) for component-scoped, dynamic styles.
- Colocate styles with components. Use the `styled` API or `css` prop for styling.
- Use `styled()` at module level for typed styled components — inline `css()` in render only for dynamic styles that depend on props.
- Use theme objects for design tokens: colors, spacing, typography, breakpoints.
- Use `ThemeProvider` for app-wide theming and dark mode support.
- Use tagged template literals (`styled.div`) or object syntax (`css({ color: "red" })`) consistently — pick one.
- Extract reusable styled components for design system primitives (Button, Card, Input).