I have a client who has built an app in Excel. Not good so I have been tasked with replicating it in PowerApps. The UI is very unique but the client is determined for me to keep the "Excel" UI the same if at all possible. I have replicated the table with buttons in PowerApps and am pulling the values perfectly. Everything is working correctly except one UI feature they really would like replicated. They would like the current active "Selected" button to be red. Here is what their current grid looks like:

I have replicated the look in PowerApps and it looks like this:

The OnSelect code for each button looks like this:
Set(varContainerSize,"96G");
Set(varServiceFrequency,"1");
UpdateContext({pressedButton:!pressedButton});
I set the 2 variables per the values on each button. I then add in "UpdateContext" code to switch the color of the button.
The Fill code for each button looks like this:
If(pressedButton=true, Color.Red, RGBA(62,96,170,1))
This starts off each button as blue and when it is selected it turns red just as the client wants.
Here is my challenge. I need to reset all buttons to blue first then set the color of the last clicked button to red so that only the current button is red. I have tried all kinds of things such as grouping the buttons and setting them all to blue and after that set the code above but my end result is all buttons cycle from red to blue. All buttons act as one.
Any suggestions?