.login-form {
  max-height: 0px;
  opacity: 0;
  overflow: hidden;
}

input#show_more {
  opacity: 0;
}

#show_more:checked ~ #new_user.login-form {
  opacity: 1;
  max-height: 9999px;
  transition: max-height .5s ease-in, opacity .3s ease-in;
}

#show_more:checked ~ label {
  display: none;
}

#show_more:checked ~ .oauth-links {
  flex-direction: row;
}

.oauth-links .button_to {
  width: 100%;
}