问题：
把 node 从 6.x 升级到 8.x 后，旧项目编译 scss 文件时报错：
Module build failed: Error: Missing binding D:\web\my-project\node_modules\node-sass\vendor\win32-x64-57\binding.node
Node Sass could not find a binding for your current environment: Windows 64-bit with Node.js 8.x
Found bindings for the following environments:
- Windows 64-bit with Node.js 6.x
This usually happens because your environment has changed since running `npm install`.
Run `npm rebuild node-sass --force` to build the binding for your current environment.
at module.exports (D:\web\my-project\node_modules\node-sass\lib\binding.js:15:13)
at Object.<anonymous> (D:\web\my-project\node_modules\node-sass\lib\index.js:14:35)
at Module._compile (module.js:652:30)
at Object.Module._extensions..js (module.js:663:10)
at Module.load (module.js:565:32)
at tryModuleLoad (module.js:505:12)
at Function.Module._load (module.js:497:3)
at Module.require (module.js:596:17)
at require (internal/module.js:11:18)
at Object.<anonymous> (D:\web\my-project\node_modules\sass-loader\lib\loader.js:3:14)
at Module._compile (module.js:652:30)
at Object.Module._extensions..js (module.js:663:10)
at Module.load (module.js:565:32)
at tryModuleLoad (module.js:505:12)
at Function.Module._load (module.js:497:3)
at Module.require (module.js:596:17)
原因：
升级了node版本，sass包和现在node版本不一致，
解决方法：
重新构建 node-sass，命令如下：
npm rebuild node-sass --force
如果执行完成后不报错，就可以了。
也有可能会报 gyp Error 错误：
gyp ERR! configure error
gyp ERR! stack Error: `gyp` failed with exit code: 1
....
gyp ERR! node -v v8.11.1
gyp ERR! node-gyp -v v3.6.2
就需要先卸载 node-sass，然后重新安装。
npm uninstall node-sass
npm install node-sass
