Très jolie!
Those are the words I used in a little store in France, where I was travelling decades ago with my late mother, on a whirlwind tour of Europe (highlighted by the Obberammergau Passion Play). I had taken 4 years of French in highschool and here was a chance to use it among the natives.
Well I was successful with those 2 words. The sales lady turned to me brightly and started chattering as though I was a native too. ...Sadly I could not keep up and when I tried her face fell quickly and she turned away.
Well I never had much chance to practice French either then or since then (and didn't try hard enough). So I've forgotten most of it. But I was tickled to remember that incident and use those words in an appropriate situation again.
Those really are lovely dresses!
I'm sure the shop I visited was not Traditionalist Catholic...