form.user-register-form .form-actions,
form.user-login-form .form-actions,
form.user-pass .form-actions {
  text-align: center;
}

form.user-register-form .form-actions .solo-button,
form.user-login-form .form-actions .solo-button,
form.user-pass .form-actions .solo-button {
  float: none;
}