SCSS: bootstrap import not found

[loleg]

I've tried importing lotusdocs (@v0.2.0) as a Go (go1.25.6) module, and am getting this error due to a missing module in SCSS compilation. Just following your guide.

hugo                                                                           ✔ 
Start building sites … 
hugo v0.154.2+extended+withdeploy linux/amd64 BuildDate=unknown

WARN  calling IsSet with unsupported type "invalid" (<nil>) will always return false.
Total in 371 ms
ERROR error building site: render: [en v1.0.0 guest] failed to render pages: render of "/" failed: "/home/oleg/.cache/hugo_cache/modules/filecache/modules/pkg/mod/github.com/colinwilson/lotusdocs@v0.2.0/layouts/_default/baseof.html:31:8": execute of template failed: template: index.html:31:8: executing "index.html" at <partial "head.html" .>: error calling partial: "/home/oleg/.cache/hugo_cache/modules/filecache/modules/pkg/mod/github.com/colinwilson/lotusdocs@v0.2.0/layouts/partials/head.html:28:42": execute of template failed: template: _partials/head.html:28:42: executing "_partials/head.html" at <$style.RelPermalink>: error calling RelPermalink: TOCSS: failed to transform "scss/style.scss" (text/x-scss): "/home/oleg/.cache/hugo_cache/modules/filecache/modules/pkg/mod/github.com/colinwilson/lotusdocs@v0.2.0/assets/scss/style.scss:18:1": 
File to import not found or unreadable: bootstrap/functions.

[loleg]

I will try to import as a git submodule instead.