Describe the bug

We have used the setting $theme-header-max-width: "none" to get full width headers. With the latest release, 3.6.1 we are having a build error when building the style sheets:

CssSyntaxError: postcss-csso: /Users/mbucknel/wdfn/wdfn-viz/node_modules/@uswds/uswds/packages/usa-nav/src/styles/_usa-nav.scss:486:0: Number, dimension, ratio or identifier is expected

Prior to version 3.6.1, we had no build issues. If I set the theme variable to something like "desktop", the style sheets build as expected.

Steps to reproduce the bug

1. Set $theme-header-max-width: "none". For example:

@use 'uswds-core' with (
  $theme-font-path: './fonts',
  $theme-image-path: './img',
  $theme-header-max-width: "none",
);

2. Build the style sheets with the recommended build procedure for the sass style sheets

Expected Behavior

Build works as expected

Related code

No response

Screenshots

No response

System setup

Using USWDS 3.6.1
Running the command on Mac OS 13.6, using sass: 1.68.0, postcss 8.4.31 and postcss-csso 6.0.1

Additional context

No response

Code of Conduct

• I agree to follow this project's Code of Conduct.
• I checked the current issues for duplicate bug reports.