fix: postcss compatibility issue

package.json

@@ -115,6 +115,7 @@
     "optimize-css-assets-webpack-plugin": "^5.0.1",
     "path": "^0.12.7",
     "postcss-flexbugs-fixes": "^4.1.0",
+    "postcss-safe-parser": "^4.0.1",
     "raw-loader": "^0.5.1",
     "react-dev-utils": "^5.0.2",
     "react-test-renderer": "^16.5.0",

webpack.prod.js

-const config = require('./config');
-const common = require('./webpack.common.js');
 const webpack = require('webpack');
 const merge = require('webpack-merge');
 const ManifestPlugin = require('webpack-manifest-plugin');
 const MiniCssExtractPlugin = require('mini-css-extract-plugin');
 const OptimizeCSSAssetsPlugin = require('optimize-css-assets-webpack-plugin');
+const safeParser = require('postcss-safe-parser');
 const UglifyJsPlugin = require('uglifyjs-webpack-plugin');
 const { BundleAnalyzerPlugin } = require('webpack-bundle-analyzer');
+const config = require('./config');
+const common = require('./webpack.common.js');
 
 module.exports = merge(common, {
   output: {
@@ -44,7 +45,7 @@ module.exports = merge(common, {
       }),
       new OptimizeCSSAssetsPlugin({
         cssProcessorOptions: {
-          safe: true,
+          parser: safeParser,
         },
       }),
     ],