My cats are 3-4 years old (we have three) and quite active. When the candles are on, we keep them out of the room. The place where we light is their favorite place to sit all day, in front of the window. Motzash, when we lit, one of them came racing in and almost jumped right on top of the candles. Now keeping in mind there’s a big curtain hanging right above…. bad idea.
Now, we make sure to keep both doors closed and physically blocked with a large closet on one side and a chair against the door on the other side. (Our cats are very good at opening doors…)