fix: corrected Regex pattern for client-side phone input validation

src/scripts/contact-form.js

@@ -88,7 +88,7 @@ form.addEventListener("submit", function(event) {
     }
 
     // Phone — match format: 123-456-7890
-    const phonePattern = /^(\(?\d{3}\)?[-.\s]?\d{3}[-.\s]?\d{4})$/;
+    const phonePattern = /^(\(?\d{3}\)?[-.\s]?\d{3}[\-.\s]?\d{4})$/;
     if (!phonePattern.test(phone)) {
         showError("phone", "Phone number format is invalid.");
         hasErrors = true;