webpack sass-loader build failure SassError: SassError: Invalid CSS after “

ERROR in ./front/styles/scss/base.scss (./node_modules/css-loader/dist/cjs.js!./node_modules/sass-loader/dist/cjs.js!./front/styles/scss/base.scss)
Module build failed (from ./node_modules/sass-loader/dist/cjs.js):
SassError: Invalid CSS after “… floor(math”: expected expression (e.g. 1px, bold), was “.div($grid-gutter-w”
on line 369 of node_modules/bootstrap-sass/assets/stylesheets/bootstrap/_variables.scss
from line 8 of node_modules/bootstrap-sass/assets/stylesheets/_bootstrap.scss
from line 6 of front/styles/scss/base.scss
vbar-padding-horizontal: floor(math.div($grid-gutter-width, 2)) !defa

my webpack.config.js

        {
            test: /.scss$/,
            use: [
                {
                    loader: 'style-loader'
                },
                {
                    loader: 'css-loader'
                },
                {
                    loader: 'sass-loader'
                }
            ]
        },