Error building meilipanel docker

[KrunchMuffin]

On the final build step I got this error

 > [build-stage 6/6] RUN npm run build:
#13 1.303
#13 1.303 > meilipanel@0.1.0 build
#13 1.303 > vue-cli-service build
#13 1.303
#13 1.985
#13 1.987 -  Building for production...
#13 15.92  ERROR  Error: CSS minification error: Lexical error on line 1: Unrecognized text.
#13 15.92
#13 15.92   Erroneous area:
#13 15.92 1: $colorpicker-radius / 1.75
#13 15.92 ^..^. File: css/chunk-vendors.fa174958.css
#13 15.92 Error: CSS minification error: Lexical error on line 1: Unrecognized text.
#13 15.92
#13 15.92   Erroneous area:
#13 15.92 1: $colorpicker-radius / 1.75
#13 15.92 ^..^. File: css/chunk-vendors.fa174958.css
#13 15.92     at /app/node_modules/@intervolga/optimize-cssnano-plugin/index.js:106:21
#13 15.92     at async Promise.all (index 1)
------
executor failed running [/bin/sh -c npm run build]: exit code: 1
ERROR: Service 'meilipanel' failed to build : Build failed

Any ideas?