🐛 [BUG]V5版本 启动 报错 Variable @layout-body-background is undefined

[cxyxscn]

🐛 bug 描述

依赖列表
"dependencies": {
"@ant-design/icons": "^4.5.0",
"@ant-design/pro-descriptions": "^1.9.0",
"@ant-design/pro-form": "^1.43.0",
"@ant-design/pro-layout": "^6.32.0-beta.4",
"@ant-design/pro-table": "^2.56.0",
"@umijs/route-utils": "^2.0.4",
"antd": "^4.17.0",
"classnames": "^2.2.6",
"lodash": "^4.17.11",
"moment": "^2.25.3",
"omit.js": "^2.0.2",
"rc-menu": "^9.0.13",
"rc-util": "^5.14.0",
"react": "^17.0.0",
"react-dev-inspector": "^1.1.1",
"react-dom": "^17.0.0",
"react-helmet-async": "^1.0.4",
"umi": "^3.5.0",
"umi-serve": "^1.9.10"
},
"devDependencies": {
"@ant-design/pro-cli": "^2.0.2",
"@playwright/test": "^1.16.3",
"@types/express": "^4.17.0",
"@types/history": "^4.7.2",
"@types/jest": "^26.0.0",
"@types/lodash": "^4.14.144",
"@types/react": "^17.0.0",
"@types/react-dom": "^17.0.0",
"@types/react-helmet": "^6.1.0",
"@umijs/fabric": "^2.6.2",
"@umijs/openapi": "^1.3.0",
"@umijs/plugin-blocks": "^2.0.5",
"@umijs/plugin-esbuild": "^1.0.1",
"@umijs/plugin-openapi": "^1.2.0",
"@umijs/preset-ant-design-pro": "^1.2.0",
"@umijs/preset-dumi": "^1.1.7",
"@umijs/preset-react": "^1.8.17",
"@umijs/yorkie": "^2.0.3",
"carlo": "^0.9.46",
"cross-env": "^7.0.0",
"cross-port-killer": "^1.1.1",
"detect-installer": "^1.0.1",
"enzyme": "^3.11.0",
"eslint": "^7.1.0",
"express": "^4.17.1",
"gh-pages": "^3.0.0",
"jsdom-global": "^3.0.2",
"lint-staged": "^10.0.0",
"mockjs": "^1.0.1-beta3",
"prettier": "^2.3.2",
"puppeteer-core": "^8.0.0",
"stylelint": "^13.0.0",
"swagger-ui-react": "^3.52.3",
"typescript": "^4.2.2"
},