import { CssVarsProvider, extendTheme } from '@mui/joy/styles'; import Box from '@mui/joy/Box'; const customTheme = extendTheme({ typography: { h1: { // `--joy` is the default CSS variable prefix. // If you have a custom prefix, you have to use it instead. // For more details about the custom prefix, go to https://mui.com/joy-ui/customization/using-css-variables/#custom-prefix background: 'linear-gradient(-30deg, var(--joy-palette-primary-700), var(--joy-palette-primary-400))', // `Webkit*` properties must come later. WebkitBackgroundClip: 'text', WebkitTextFillColor: 'transparent', }, }, }); export default function CustomTypographyLevel() { return ( theme.typography.h1}>This is a gradient h1 ); }