#auth_submit .loader {
  width: 31px;
  height: 31px;
  position: relative;
  display: block;
  margin: 0 auto;
}
#auth_submit .loader img {
  width: 100%;
  height: auto;
}

#auth_submit .login, #auth_submit.sent .loader {
  display: block;
}
#auth_submit .loader, #auth_submit.sent .login {
  display: none;
}