message: fix: restore v4 default background color '#FAFAFA'
diff: @@ -17,6 +17,7 @@ const colors = {
  },
  gray: {
  main: '#F5F5F5',
  + background: '#FAFAFA',
  },
  }
  @@ -32,6 +33,9 @@ export const themeOptions: ThemeOptions = {
  main: colors.yellow.main,
  light: colors.gray.main,
  },
  + background: {
  + default: colors.gray.background,
  + },
  },
  shape: {
  borderRadius: 3,
  