Which Baby Gate Is The Safest For The Top Of A Staircase?

I’m just curious which baby gates you all suggest for the top of a staircase? We have one mounted now but I don’t find it sturdy/safe enough now that my son is older and pulling on it. He’s 18 months old and attempts to climb on everything these days. I’m worried he will eventually learn to climb out of his crib and head right for those stairs. I would appreciate suggestions ones you do like or ones I should avoid.
Thanks so much!