Can you give some more detail on specifically what you've tried and how it's failing to operate as anticipated? I'm able to get this to work like so:

Here's my rule:

Make sure that when you're picking your controls/items for your "Condition" that you're picking from the "Named Controls" segment, not the "Item Properties." The named controls is the value of the actual control and changes when that changes. Item Properties is the value of the column for the item and thus, will not change until the item is saved.

You're changing the label. I want the actual amount to be red. It's in a repeating section so some values may be equal and some not. I want the rows != to be red. My rule is set up just like yours except it's set up on the text box, not the label.

Ahh, I think that this can only be done to the label. Even custom CSS applied to the actual fields isn't in effect while editing (ex, text box has CSS class of someTextBox and in my CSS for the form if have someTextBox { color: #ffffff }, it's still black when editing, but white if the form is viewed). JS may be the only way to accomplish what you're after.

Maybe just changing the label that is the column "header" will be sufficient. I'll try some different options. Thanks!