#login-popup {
  position:fixed;
  top:0;
  left:0;
  width:100%;
  height:100%;
  background:rgba(0,0,0,0.7);
  z-index:9999;
}

#login-popup .popup-overlay {
  width:100%;
  height:100%;
  position:absolute;
}

#login-popup .popup-close {
  position:absolute;
  top:10px;
  right:10px;
  background:none;
  border:none;
  color:white;
  font-size:24px;
  cursor:pointer;
}

#login-popup .login-form, 
#login-popup .register-form {
  flex: 1;
}