* "Mieux pour toi" translates to "Good for you" or "That's good for you." This expresses a neutral or slightly positive sentiment.
* "Alors cava" is a bit trickier. "Alors" means "so" or "then". "Cava" is a shortened version of "ça va," which means "it's going" or "everything is okay."
Putting it together, "mieux pour toi alors cava" could mean:
* "Good for you, then everything is okay."
* "That's good for you, so it's all good."
* "Good for you, things are fine."
The phrase is generally used to acknowledge someone's good news or positive situation and also to convey that everything is alright on the speaker's end.