diff --git a/app/templates/index.html b/app/templates/index.html
index 53972fb..65d7a18 100644
--- a/app/templates/index.html
+++ b/app/templates/index.html
@@ -160,7 +160,7 @@ <h3><i class="fas"></i>Semester & View Options</h3>
     updateButtonStates();
 
     // Basic form validation
-    const CODE_RE = /^[A-Z]{3,4}\d{4}[A-Z]?/;
+    const CODE_RE = /^[A-Za-z]{3,4}\d{4}[A-Za-z]?/;
 
     document.getElementById('temp-form-name').addEventListener('submit', function(e) {
       e.preventDefault();