public async Task <IActionResult> OnPostAsync(string returnUrl = null)
        {
            returnUrl = returnUrl ?? Url.Content("~/");
            if (ModelState.IsValid)
            {
                var user = new ApplicationUser {
                    UserName = Input.Email, Email = Input.Email
                };
                var result = await _userManager.CreateAsync(user, Input.Password);

                if (result.Succeeded)
                {
                    //await _db.Sections.AddAsync(new Section(user.Id));
                    //await _db.SaveChangesAsync();
                    await Section.AddMainSection(_db, user.Id);

                    _logger.LogInformation("User created a new account with password.");

                    var code = await _userManager.GenerateEmailConfirmationTokenAsync(user);

                    var callbackUrl = Url.Page(
                        "/Account/ConfirmEmail",
                        pageHandler: null,
                        values: new { userId = user.Id, code = code },
                        protocol: Request.Scheme);

                    await _emailSender.SendEmailAsync(Input.Email, "Confirm your email",
                                                      $"Please confirm your account by <a href='{HtmlEncoder.Default.Encode(callbackUrl)}'>clicking here</a>.");

                    await _signInManager.SignInAsync(user, isPersistent : false);

                    return(LocalRedirect(returnUrl));
                }
                foreach (var error in result.Errors)
                {
                    ModelState.AddModelError(string.Empty, error.Description);
                }
            }

            // If we got this far, something failed, redisplay form
            return(Page());
        }