Fix Sass imports in Parcel example for Windows

[julien-deramond]

Closes #321

Description

This PR addresses issue #321.

On macOS, there are no problems—everything compiles and launches as expected. However, on Windows, we were able to replicate the issue with @louismaximepiton.

The import statement @import "bootstrap/scss/bootstrap" works correctly in our step-by-step guide because it references the bootstrap.scss file in the node_modules directory. However, when attempting something similar to the Parcel example, such as @import "bootstrap/scss/functions", it fails. This is because Parcel or the Parcel Sass Transformer cannot locate the file named _functions.scss.

(it's referenced at several locations—e.g. parcel-bundler/parcel#6002, parcel-bundler/parcel#3704, etc.)

While Sass handles this by default on other systems, it fails to do so with Parcel on Windows for these specific imports.

We considered three potential solutions to fix this issue for Windows users:

1. Use @import "~/node_modules/bootstrap/scss/functions";
2. Use @import "../../node_modules/bootstrap/scss/functions";
3. Use @import "~/node_modules/bootstrap/scss/_functions";

We opted for the simplest approach, which doesn't require users to know the exact filenames (including underscores) or the precise relative paths.

Upstream Parcel Guide

The upstream documentation for Parcel says:

You can also import our stylesheets individually if you want. Read our Sass import docs for details.

In the link, we use a relative path to target the files, so it'll work as well. I don't think it's needed to modify the upstream guide.

[louismaximepiton]

Works for me

[julien-deramond]

@XhmikosR FYI, if you want to double-check this PR. Otherwise, it's ready to be merged :)

[XhmikosR]

Weird that parcel doesn't work, but I confirm this fixes the issue on Windows.