Custom Dashboard that informs of unread email(s) in a specific O365 account and starts a countdown for each email individually

Hi there, I am looking for a dashboard that I can display on a big screen. This screen will be on a wall at the customer service team. My business goal: get our response time on incoming emails down by directly seeing each new (unread) email and see a countdown displaying the time an email is sitting unread in the mailbox. This countdown should start at 5 minutes and count backwards to zero. What i want to do: I want to install a big screen where every new email is displayed with a corresponding individual countdown from 5 minutes to zero. Once a email is read, the countdown stops and vanishes from the screen. What we do and use today: We use Office365 and have a specific email-address where we receive those emails that need to be monitored. Today everyone looks into this email folder every now and then. And selects an email to respond to without feeling the need to hurry up. How it should look like: see attached file. Each box represents one specific email. A new email adds a box at the upper left corner. Once the email is read, the box disappears. The closer the timer gets to zero, the "redder" the box gets.