The blue bathmat already looks good to me so I voted blue.

I would go with Zen.

Those colors look way more saturated once they go up^^^

As tracefloyd says, I think both of those colors are too dark. Move up the paint chip to lighter versions of those colors and look at them against the floor and shower curtain if you're keeping it. We can't tell from the picture what color the floor is or what the shower curtain looks like. Either of those colors at 50% saturation will still be colorful enough to provide contrast with the tile.

Sometimes contrast isn’t the ideal choice and given the softness of the shower curtain, I’d lean towards more of a robin’s egg blue. Place a white mat over tub when not in use and add a framed print over toilet for the impact you are looking for. It’s important to think big picture when choosing paint so as to create a well coordinated space.