Client bundle compiled with errors therefore further build is impossible.

[pincman]

buiding error for mixins https://github.com/postcss/postcss-mixins

assets/css/styles.96b8f0e6.css from Css Minimizer plugin
/home/pincman/code/test/assets/css/styles.96b8f0e6.css:4480:11: Unknown word [assets/css/styles.96b8f0e6.css:4480,11]
assets/css/styles.864b3238.css from Css Minimizer plugin
/home/pincman/code/test/assets/css/styles.864b3238.css:4480:11: Unknown word [assets/css/styles.864b3238.css:4480,11]
[ERROR] Client bundle compiled with errors therefore further build is impossible.
 ELIFECYCLE  Command failed with exit code 1.