==========================
Function calls
==========================

a {
  color: rgba(0, 255, 0, 0.5);
}

---

(stylesheet
  (rule_set
    (selectors (tag_name))
    (block
      (declaration
        (property_name)
        (call_expression (function_name) (arguments
          (integer_value)
          (integer_value)
          (integer_value)
          (float_value)))))))

============================
Color literals
============================

a {
  b: #fafd04;
  c: #fafd0401;
}

---

(stylesheet
  (rule_set
    (selectors (tag_name))
    (block
      (declaration (property_name) (color_value))
      (declaration (property_name) (color_value)))))