[PineScript] Build Me Input Box For Choosing Date & Change The Background Color Based On Date Choosen

I'm trying to make input box in tradingview for choose Starting Month & Year,
Also input box for choose Ending Month & Year.

Example Input :-
1. Input Box Starting Month & Year = January 2021
2. Input Box Ending Month & Year = January 2022

After choose the Month & Year both,
The color background at the drawing chart will change in every 3 month

Example Background Color :-
1. January - April = Grey Background
2. April - July = Yellow Background
3. July - October = Grey Background
4. October - January = Yellow Background

I'm willing to discuss more and will share and go over this project with you.

For your information, I got some basic pine script. And I was able to do the input box.

My code is doing well for the input.

However, I'm having issue with the coding for the background color. It was not change with criteria I want.

Thank you!