Take off the tank lid. Flush the toilet and observe carefully. Your flapper is fine, so no need to be concerned with that. There is a tiny tube that goes from the fill valve into the overflow tube and is secured there by a clip. Make sure it is sending water into the overflow tube because that's what refills the bowl. If that retainer clip comes loose, water could spray anywhere.
Also make sure water isn't spraying up from the fill valve that would hit the underside of the tank lid, as it would leak down the outside of the tank onto the floor. The float should rise as the water fills, and if it doesn't it is either getting hung up by something, or it has become partially waterlogged (Which means it has a leak in it, and needs to be replaced).
If the water rises to the level it should be, and everything seems to be working fine, then it's possible the likely culprit is the wax ring that the toilet sits on, and you will see the leaking around the base of the toilet mainly when you flush it.