Error in plugin 'sass'
Message:
    ../node_modules/bootstrap/scss/_custom-forms.scss
Error: Undefined variable: "$custom-control-gutter".
        on line 15 of ../node_modules/bootstrap/scss/_custom-forms.scss
        from line 52 of koha-tmpl/opac-tmpl/bootstrap/css/src/_common.scss
        from line 1 of koha-tmpl/opac-tmpl/bootstrap/css/src/opac.scss
>>   padding-left: $custom-control-gutter + $custom-control-indicator-size;

   ----------------^

[17:22:47] Finished 'build' after 148 ms