The Noob's (in)complete guide to CSS for Hubitat

Maybe adapt my suggestion for the linear-gradient above:

div.switch[style*="background-color: rgba(250, 242, 0, 0.87)"] { 
  background: linear-gradient(red,yellow);
}

change it to something like:

#tile-1[style*="background-color: rgba(200, 0, 0, 0.67)"] { 
  background-color: rgba(0, 200, 0, 0.67) !important;
}
#tile-1[style*="background-color: rgba(0, 200, 0, 0.67);"] { 
  background-color: rgba(200, 0, 0, 0.67)  !important;
}

That should switch the color from red to green and green to red. Might need to add !important to the end of background-color if it doesn't work. Also those are the default colors, it would be different if you've changed them.

I edited this after trying it out a bit. This should work OK now. Change the #tile-1 to whatever your tile number is, and if your colors aren't defaults, change the colors based on what's used in the tile style tag.