Incorrect highlighting w/ css vars, hex color format

[rnmeow]

To reproduce:

$color-scheme-light {
    --text-color: #3f3f3f;
    --text-color-hover: black;
    --link-color: #13348f;
    --link-color-hover: #071438;
    --semitransp-bg-color: rgba(245, 245, 245, .2);
    --more-info-btn-color: #0f2a75;
    --navbar-text-color: #474747;
}
$color-scheme-dark {
    --text-color: #dadada;
    --text-color-hover: #8e8e8e;
    --link-color: #97b3ff;
    --link-color-hover: #aaa;
    --semitransp-bg-color: rgba(60, 60, 60, .2);
    --more-info-btn-color: #79f;
    --navbar-text-color: #d2d2d2;
}

Current behavior:

Highlighting confusion w/ CSS variables and hex color:

Expected behavior:

They displays neatly.

Environment information:

• Stylus extension version: v1.16.0
• VS Code version: 1.69.1
• operating system: Arch Linux (kernel: 5.18.6-arch1-1)