Gates are not even an obstacle for kitties. I have to literally quarantine them if I want to get anything done. And then I see little paws under the door...
I had a similar problem with the puppy gate. Solitare could sail over it with about 8 inches to spare.
I started leaning it instead of using the compression spring.
After a couple of loud crashes to the floor, they don't want to get within a foot of it.