what is wrong with this color: $dark;??

[lxregistry]

trafficstars

` error in ./assets/styles/app.scss 1:16:11 PM

Module build failed (from ./node_modules/mini-css-extract-plugin/dist/loader.js): HookWebpackError: Module build failed (from ./node_modules/sass-loader/dist/cjs.js): Undefined variable. ╷ 24 │ color: $dark; │ ^^^^^ ╵ node_modules/bootswatch/dist/flatly/_bootswatch.scss 24:12 @use assets/styles/app.scss 9:1 `

@import "~bootswatch/dist/flatly/variables";
@import "~bootstrap/scss/bootstrap";
@import "~bootswatch/dist/flatly/bootswatch";