fix: remove template strings from parsing regex (#249)

fixes weird regex templated string issue

src/format-input.ts

@@ -90,13 +90,14 @@ const CSS_INTEGER = '[-\\+]?\\d+%?';
 const CSS_NUMBER = '[-\\+]?\\d*\\.\\d+%?';
 
 // Allow positive/negative integer/number.  Don't capture the either/or, just the entire outcome.
-const CSS_UNIT = `(?:${CSS_NUMBER})|(?:${CSS_INTEGER})`;
+const CSS_UNIT = '(?:' + CSS_NUMBER + ')|(?:' + CSS_INTEGER + ')';
 
 // Actual matching.
 // Parentheses and commas are optional, but not required.
 // Whitespace can take the place of commas or opening paren
-const PERMISSIVE_MATCH3 = `[\\s|\\(]+(${CSS_UNIT})[,|\\s]+(${CSS_UNIT})[,|\\s]+(${CSS_UNIT})\\s*\\)?`;
-const PERMISSIVE_MATCH4 = `[\\s|\\(]+(${CSS_UNIT})[,|\\s]+(${CSS_UNIT})[,|\\s]+(${CSS_UNIT})[,|\\s]+(${CSS_UNIT})\\s*\\)?`;
+const PERMISSIVE_MATCH3 = '[\\s|\\(]+(' + CSS_UNIT + ')[,|\\s]+(' + CSS_UNIT + ')[,|\\s]+(' + CSS_UNIT + ')\\s*\\)?';
+const PERMISSIVE_MATCH4 =
+  '[\\s|\\(]+(' + CSS_UNIT + ')[,|\\s]+(' + CSS_UNIT + ')[,|\\s]+(' + CSS_UNIT + ')[,|\\s]+(' + CSS_UNIT + ')\\s*\\)?';
 
 const matchers = {
   CSS_UNIT: new RegExp(CSS_UNIT),