diff --git a/Lab01/app/templates/_base.tmpl b/Lab01/app/templates/_base.tmpl
index b86efb1..bdf4441 100644
--- a/Lab01/app/templates/_base.tmpl
+++ b/Lab01/app/templates/_base.tmpl
@@ -71,7 +71,7 @@
                 <input type="text" class="form-control" id="username"
                        aria-describedby="inputGroupPrepend" required>
                 <div class="invalid-feedback">
-                    Please choose a username.
+                    Please choose a username. It cannot include whitespaces.
                 </div>
             </div>
         </div>
@@ -79,7 +79,7 @@
             <label for="password" class="form-label">Password</label>
             <input type="password" class="form-control" id="password" aria-describedby="passwordHelp" required>
             <div id="invalidPassword" class="invalid-feedback">
-                Please choose a password.
+                Please choose a password. It cannot include whitespaces.
             </div>
         </div>
         <div class="col-12">
@@ -169,21 +169,32 @@
 {{define "formScripts"}}
     <script>
         let form = document.querySelector('.needs-validation')
+
+        function hasWhiteSpace(s) {
+            return s.indexOf(' ') >= 0;
+        }
+
         if (form) {
             form.addEventListener('submit', function (event) {
                 if (!form.checkValidity()) {
                     event.preventDefault();
                     event.stopPropagation();
                 } else {
+                    let invalid = false;
                     event.preventDefault();
                     let data = new FormData();
                     let form_element = document.getElementsByClassName('form-control');
                     for (let i = 0; i < form_element.length; i++) {
                         data.append(form_element[i].id, form_element[i].value);
                     }
-                    submitForm(data);
+                    for (let i = 0; i < form_element.length; i++) {
+                        if (hasWhiteSpace(form_element[i].value)) {
+                            form_element[i].classList.add('is-invalid')
+                            invalid = true;
+                        }
+                    }
+                    !invalid && submitForm(data);
                 }
-                form.classList.add('was-validated');
             }, false);
         }
     </script>