Syntax Error: SassError: Undefined variable.

[dybxin]

Question（提问）

Steps to reproduce（问题复现步骤）

WAIT Compiling... 5:15:29 PM

98% after emitting CopyPlugin

ERROR Failed to compile with 1 error 5:15:30 PM

error in ./src/styles/sidebar.scss

Syntax Error: SassError: Undefined variable.
╷
6 │ margin-left: $sideBarWidth;
│ ^^^^^^^^^^^^^
╵
/src/styles/sidebar.scss 6:18 root stylesheet

@ ./src/styles/sidebar.scss 4:14-227 15:3-20:5 16:22-235
@ ./src lazy ^./.*$ namespace object
@ ./src/store/modules/router.js
@ ./src/store/index.js
@ ./src/main.js
@ multi (webpack)-dev-server/client?http://192.168.1.48:8080&sockPath=/sockjs-node (webpack)/hot/dev-server.js ./src/main.js

Screenshot or Gif（截图或动态图）

Link to minimal reproduction（最小可在线还原demo）

Other relevant information（格外信息）

• Your OS: ubuntu
• Node.js version:v14.17.0
• vue-element-admin version:master