Added error messages for invalid login

src/login.html

@@ -32,6 +32,7 @@
                                     <label for="loginPassword" class="mb-1">Password</label>
                                     <input class="form-control mb-4" id="loginPassword" type="password" placeholder="Password" name="password">
                                 </div>
+                                <label for="invalid-login" id="invalid-login" class="text-center w-100 pb-2" style="color: red;"></label>
                                 <button type="submit" class="btn btn-outline-dark mx-auto d-block py-2" id="submitLogin">Login</button>
                           </form>
                       </div>

src/login.js

@@ -43,16 +43,15 @@ function loginUser(username, password) {
               resolve(user);
             }
             else {
-              alert('Invalid Username or Password');
+              document.getElementById('invalid-login').innerHTML = 'Invalid login credentials!';
               reject(new Error('Inavlid username or Password'));
             }
           } else {
-            alert('Invalid Username or Password');
+            document.getElementById('invalid-login').innerHTML = 'Invalid login credentials!';
             reject(new Error('Invalid username or Password'));
           }
       } catch(err) {
         console.error(err);
-        alert(err);
         reject(err);
       }
     })