# Baseui responsive typography theme.js ```jsx // Create custom theme import { createTheme, lightThemePrimitives } from 'baseui'; // Responsive typography const overrides = { typography: { HeadingXXLarge: { // H1 [mediaQuery.small]: { fontSize: '28px', }, [mediaQuery.medium]: { fontSize: '36px', }, [mediaQuery.large]: { fontSize: '48px', }, }, }, }; const customTheme = createTheme(lightThemePrimitives, overrides); ``` Root.js ```tsx // Pass custom theme to theme provider <ThemeProvider theme={customTheme}> {...} </ThemeProvider> ```