fix: remove mui theme provider (#2055)

packages/component/src/components/affine-loading/index.tsx

@@ -1,4 +1,4 @@
-import { useTheme } from '@mui/material';
+import { useTheme } from 'next-themes';
 import type { FC } from 'react';
 
 import { InternalLottie } from '../internal-lottie';
@@ -16,8 +16,8 @@ export const AffineLoading: FC<AffineLoadingProps> = ({
   autoplay = false,
   autoReverse = false,
 }) => {
-  const theme = useTheme();
-  const isDark = theme.palette.mode === 'dark';
+  const { theme } = useTheme();
+  const isDark = theme === 'dark';
   return (
     <InternalLottie
       key={isDark ? 'dark' : 'light'}

packages/component/src/components/workspace-card/styles.ts

@@ -48,7 +48,7 @@ export const StyledCard = styled('div')<{
     ...displayFlex('flex-start', 'flex-start'),
     marginBottom: '24px',
     transition: 'background .2s',
-    background: theme.palette.mode === 'light' ? '#FFF' : '#2C2C2C',
+    background: 'var(--affine-background-primary-color)',
     position: 'relative',
     ':hover': {
       background: 'var(--affine-hover-color)',