Node Sass version 6.0.1 is incompatible with ^4.0.0.

Node sass version 6.0.0 is not compatible with ^ 4.0.0
1. Uninstall the previous version of node sass
NPM install node sass
2. Install version 4.0.0 after uninstall
NPM install node-sass@4.14.1
Here may fail, because you install the Taobao image problem.

If it fails, reload the Taobao image
NPM install – G cnpm — registry= https://registry.npm.taobao.org
After reassembling, perform the second step again

npm install node-sass@4.14.1

Restart the project NPM run dev

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