How to right-align a label, revisited (suggestion didn't work)

Adding this .CSS style:

.rightalignlabel {
  text-align="right";
  align="right";
}

I tried align="right" even though align is not in the drop-down list that appears when you create a new .CSS class because that's what a response to my original post recommended, but it didn't work any better (or worse) than text-align.

Of course, I assigned the rightalignlabel class to the label in question.
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