Can't access global SASS variables from my component - css

Question

In my Nuxt app I load all my SASS thus:
css: [
'~assets/scss/main.scss'
],
It works perfectly, except when I'm trying to use some SASS variable from within a component.
<style lang="scss">
.container {
background-color: $white;
}
</style>
In this case I get this error message:
SassError: Undefinied variable: $white
Yet, all of the SCSS contained in the SASS file where the variable is defined works throughout the app.
It is as if the app as a whole knew these files, but each individual component doesn't.
What's going on?

Answer 1

Most of the other answers don't take into account that Nuxt.js hides all the Webpack setup and forces you to do everything through nuxt.config.js.
My guess is that Webpack isn't compiling all the SCSS declarations together and therefore can't find the variable.
It's been a few months since I had this issue so things may have changed but here goes...
Make sure you have the correct Node packages installed (Nuxt DID NOT do this by default for me) npm i -D node-sass sass-loader
Add your CSS & SCSS files to the css: [] section of nuxt.config.js Order matters here so make sure things like variables are added before things that use them if you have separate files.
If you're using layouts (I think that's the default Nuxt setup) make sure that layouts/default.vue has a <style lang="sass"></style> block in it. If I remember correctly this can be empty but had to exist. I only have one layout but it may need to exist in all of them.
If all that seems like too much of a pain, there's a Nuxt Plugin that takes most of the work/management out of that process. Nuxt Style Resources Module

Answer 2

The confusing part is that:
styles from scss files CAN be loaded like this
//nuxt.config.js
css: [
'~assets/scss/main.scss'
],
//global scss file
$varcolor: black
h1{background: $varcolor}
BUT
the variables inside CAN NOT be used inside a component
//inside component
.component {background: $varcolor} // DOES NOT WORK
I also suggest the use of the nuxt style resource module:
https://github.com/nuxt-community/style-resources-module

Answer 3

new founded solution, checked and it's work. Founded here
add #nuxtjs/style-resources
export default {
css: [
'vendor.min.css'
],
modules: [
'#nuxtjs/style-resources'
],
//You will have to add this new object if it doesn't exist already
styleResources: {
scss: ['./assets/scss/main.scss'] // here I use only main scss with globally styles (variables, base etc)
},
}
it's strange, but if u change tilda (~) to dot(.), it's help for someone
from css: [ '~assets/scss/main.scss' ] to css: [ './assets/scss/main.scss' ]
this solution finded here

Answer 4

Us should either load the scss in your component
<style lang="sass">
#import 'path/to/your/_variable.scss'; // Using this should get you the variables
.my-color {
color: $primary-color;
}
Or adding the following to you to your vue.config.js
module.exports = {
css: {
loaderOptions: {
sass: {
data: `#import "#/pathto/variables.scss";`
}
}
}
};

Answer 5

Ref:
SassError: Undefinied variable: $white
Each <style lang="scss"> is compiled individually. You need to #import the file which defines $white into your component before the parser knows what $white means.
This is why most frameworks keep their variables in a _variables.scss file which is imported in all the other SCSS files/contexts.
The _variables.scss is not even loaded in the page, because in most cases it doesn't actually contain any rules. It only contains variable definitions which are imported into other .scss files, which output .css.
Ref:
Yet, all of the SCSS contained in the SASS file where the variable is defined works throughout the app.
If you import an SCSS file in your vue.config.js the output will be an ordinary <style> tag. Its contents will be generated at compile/build time and will result into some CSS (which apply to the entire document).
Unless specifically imported into the component SCSS, (using an #import command), the compiler will not know what $white means.
There is an important distinction to make between compilation context and browser context. Compilation happens at compile time (most likely in node-sass). Browser context is the actual browser, which only understands the CSS resulted from compilation.
How does Vue only apply style rules to the parent and not to the children with the same class? That's achieved by scoping.
It means applying a custom data-v-{key} attribute to all selectors in the generated <style> tag and to all elements the style should apply to.
See this example and inspect it using your web console: https://codesandbox.io/s/vue-template-ge2hb
It produces this markup:
As you can see, the scoped CSS has an extra [data-v-763db97b] added to the selector, which means it only applies to elements having that data attribute.