fix: replace CSS4 rgb() notation with rgba() for SCSS compiler compat

The space-separated rgb(r g b / a) syntax is not supported by the SCSS
compiler used in CI. Replaced with rgba(r, g, b, a) and disabled the
conflicting stylelint color-function-notation and alpha-value-notation
rules to allow legacy notation.

Author: Pyth3rEx

.stylelintrc.yml

@@ -25,5 +25,9 @@ rules:
   # Descending specificity false positives with SCSS nesting
   no-descending-specificity: null
 
+  # SCSS compiler does not support CSS4 space-separated color notation
+  color-function-notation: null
+  alpha-value-notation: null
+
   # Allow // single-line comments
   scss/double-slash-comment-empty-line-before: null

_sass/custom.scss

@@ -572,7 +572,7 @@ summary.series-header {
 }
 
 .find-match {
-  background: rgb(204 34 0 / 25%);
+  background: rgba(204, 34, 0, 0.25);
   color: $text;
   border-radius: 1px;
 }