Alpha-1729/ESP_WiFi_Captive_Portal ? reverse-engineered prompt

Build me an ESP8266 captive portal for a demo access point that opens a simple web page when someone connects. I want it to work on a NodeMCU, show a fake login style page for testing, and let me change the WiFi name from the portal itself.

It should save the SSID and any demo entries in the device memory so they still show up after reboot, and I should be able to clear the saved data from a page or route. Make the LED blink a few times when a form is submitted so I can tell it worked.

Please keep it easy to flash from Arduino IDE, and make the pages simple and mobile friendly. If you need current ESP8266 docs or library details, look them up online first.