"sass": "1.65.1" Error: This variable was not declared with !default in the @used module.

[sysmat]

• using sass

@use "./node_modules/@picocss/pico/scss/pico.scss" with ( // overwrite pico
    $primary-500: #E65A00,
    $primary-600: #C54100,
    $primary-700: #A52D00);

• Error: This variable was not declared with !default in the @used module.
• this working fine with sass 1.64.2

[Goodwine]

Which pico version? Can you have a minimal repro that doesn't use pico?

[sysmat]

"@picocss/pico": "^2.0.0-alpha1",

[sysmat]

• @Goodwine stackblitz url: https://stackblitz.com/edit/vitejs-vite-pico?file=pico.scss
• in terminal run: npm run dev and you will see error
• npm dev script use sass and vite to run dev server for index where i use style.css
• in style.scss I use pico

[ntkme]

It appears to be a breaking change between pico 1.x and 2.x, which has nothing to do with sass version.

[Goodwine]

As @ntkme mentions, the issue is a breaking change in picocss. I recommend writing a script that can repro the issue and using git-bisect on picocss to identify when the issue started.

https://git-scm.com/docs/git-bisect